Methods of enhancing sweet taste of compositions using substituted thieno{2,3-D}pyrimidines

ABSTRACT

The present invention provides, in part, substituted thieno[2,3-d]pyrimidines and methods of contacting compositions with such compounds to enhance the sweet taste of said compositions.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/836,074, filed Aug. 8, 2007, which is a continuation-in-part of U.S.patent application Ser. No. 11/760,592, filed Jun. 8, 2007. Thisapplication is also related to U.S. application Ser. No. 12/663,634,filed Dec. 8, 2009, which is a U.S. National Stage application ofInternational Application No. PCT/US2008/065650, filed on Jun. 3, 2008and published as WO 2008/154221, which claims priority to U.S. patentapplication Ser. No. 11/760,592, filed Jun. 8, 2007; U.S. patentapplication Ser. No. 11/836,074, filed Aug. 8, 2007; and U.S. PatentProvisional Application Ser. No. 61/027,410, filed Feb. 8, 2008. Thecontents of the above applications arc hereby incorporated by referencein their entireties for all purposes.

BACKGROUND OF THE INVENTION

The taste system provides sensory information about the chemicalcomposition of the external world. Taste transduction is one of the mostsophisticated forms of chemical-triggered sensation in animals.Signaling of taste is found throughout the animal kingdom, from simplemetazoans to the most complex of vertebrates. Sensations associated withtaste are thought to involve distinct signaling pathways mediated byreceptors, i.e., metabotropic or ionotropic receptors. Cells whichexpress taste receptors, when exposed to certain chemical stimuli,elicit taste sensation by depolarizing to generate an action potential,which is believed to trigger the sensation. This event is believed totrigger the release of neurotransmitters at gustatory afferent neuronsynapses, thereby initiating signaling along neuronal pathways thatmediate taste perception.

As such, taste receptors specifically recognize molecules that elicitspecific taste sensation. These molecules are also referred to herein as“tastants.” Many taste receptors belong to the 7-transmembrane receptorsuperfamily, which are also known as G protein-coupled receptors(GPCRs). Other tastes are believed to be mediated by channel proteins. Gprotein-coupled receptors control many physiological functions, such asendocrine function, exocrine function, heart rate, lipolysis,carbohydrate metabolism, and transmembrane signaling.

For example, family C of G-protein coupled receptors (GPCRs) from humanscomprises eight metabotropic glutamate (mGlu(1-8)) receptors, twoheterodimeric gamma-aminobutyric acid(B) (GABA(B)) receptors, acalcium-sensing receptor (CaR), three taste (T1R) receptors, apromiscuous L-alpha-amino acid receptor (GPRC6A), and five orphanreceptors. The family C GPCRs are characterized by a largeamino-terminal domain, which binds the endogenous orthosteric agonists.Additionally, allosteric modulators which bind to the seventransmembrane domains of the receptors have also been reported.

In general, upon ligand binding to a GPCR, the receptor presumablyundergoes a conformational change leading to activation of a G protein.G proteins are comprised of three subunits: a guanyl nucleotide bindingα-subunit, a β-subunit, and a γ-subunit. G proteins cycle between twoforms, depending on whether GDP or GTP is bound to the α-subunit. WhenGDP is bound, the G protein exists as a heterotrimer: the G_(αβγ),complex. When GTP is bound, the α-subunit dissociates from theheterotrimer, leaving a G_(βγ), complex. When a G_(αβγ) complexoperatively associates with an activated G protein-coupled receptor in acell membrane, the rate of exchange of GTP for bound GDP is increasedand the rate of dissociation of the bound G_(α) subunit from the G_(αβγ)complex increases. The free G_(α) subunit and G_(βγ) complex are thuscapable of transmitting a signal to downstream elements of a variety ofsignal transduction pathways. These events form the basis for amultiplicity of different cell signaling phenomena, including forexample the signaling phenomena that are identified as neurologicalsensory perceptions such as taste and/or smell.

Mammals are believed to have five basic taste modalities: sweet, bitter,sour, salty, and umami (the taste of monosodium glutamate). Numerousphysiological studies in animals have shown that taste receptor cellsmay selectively respond to different chemical stimuli. In mammals, tastereceptor cells are assembled into taste buds that are distributed intodifferent papillae in the tongue epithelium. Circumvallate papillae,found at the very back of the tongue, contain hundreds to thousands oftaste buds. By contrast, foliate papillae, localized to the posteriorlateral edge of the tongue, contain dozens to hundreds of taste buds.Further, fungiform papillae, located at the front of the tongue, containonly a single or a few taste buds.

Each taste bud, depending on the species, contains 50-150 cells,including precursor cells, support cells, and taste receptor cells.Receptor cells are innervated at their base by afferent nerve endingsthat transmit information to the taste centers of the cortex throughsynapses in the brain stem and thalamus. Elucidating the mechanisms oftaste cell signaling and information processing is important tounderstanding the function, regulation, and perception of the sense oftaste.

The gustatory system has been selected during evolution to detectnutritive and beneficial compounds as well as harmful or toxicsubstances. Outside the tongue, expression of Gα_(gust) has also beenlocalized to gastric and pancreatic cells, suggesting that ataste-sensing mechanism may also exist in the gastrointestinal (GI)tract. Expression of taste receptors has also been found in the liningof stomach and intestine, suggesting that taste receptors may play arole in molecular sensing of therapeutic entities and toxins.

Complete or partial sequences of numerous human and other eukaryoticchemosensory receptors are currently known. Within the last severalyears, a number of groups including the present assignee Senomyx, Inc.have reported the identification and cloning of genes from two GPCRfamilies that are involved in taste modulation and have obtainedexperimental results related to the understanding of taste biology.These results indicate that bitter, sweet and amino acid taste, alsoreferred as umami taste, are triggered by activation of two types ofspecific receptors located at the surface of taste receptor cells (TRCs)on the tongue i.e., T2Rs and T1Rs. It is currently believed that atleast 26 to 33 genes encode functional receptors (T2Rs) for bittertasting substances in human and rodent respectively.

By contrast there are only 3 T1Rs, T1R1, T1R2 and T1R3, which areinvolved in umami and sweet taste. Structurally, the T1R and T2Rreceptors possess the hallmark of G protein-coupled receptors (GPCRs),i.e., 7 transmembrane domains flanked by small extracellular andintracellular amino- and carboxyl-termini respectively.

T2Rs have been cloned from different mammals including rats, mice andhumans. T2Rs comprise a novel family of human and rodent Gprotein-coupled receptors that are expressed in subsets of tastereceptor cells of the tongue and palate epithelia. These taste receptorsare organized in clusters in taste cells and are genetically linked toloci that influence bitter taste. The fact that T2Rs modulate bittertaste has been demonstrated in cell-based assays. For example, mT2R-5,hT2R-4 and mT2R-8 have been shown to be activated by bitter molecules inin vitro gustducin assays, providing experimental proof that T2Rsfunction as bitter taste receptors. See also T2Rs disclosed in U.S. Pat.No. 7,105,650.

T1R family members in general include T1R1, T1R2, and T1R3, e.g., rT1R3,mT1R3, hT1R3, rT1R2, mT1R2, hT1R2, and rT1R1, mT1R1 and hT1R1. It isknown that the three T1R gene members T1R1, T1R2 and T1R3 formfunctional heterodimers that specifically recognize sweeteners and aminoacids. It is generally believed that T1R2/T1R3 combination recognizesnatural and artificial sweeteners while the T1R1/T1R3 combinationrecognizes several L-amino acids and monosodium glutamate (MSG),respectively. For example, co-expression of T1R1 and T1R3 in recombinanthost cells results in a hetero-oligomeric taste receptor that respondsto umami taste stimuli. Umami taste stimuli include by way of examplemonosodium glutamate and other molecules that elicit a “savory” tastesensation. By contrast, co-expression of T1R2 and T1R3 in recombinanthost cells results in a hetero-oligomeric sweet taste receptor thatresponds to both naturally occurring and artificial sweeteners.

There is a need in the art to develop various ways of identifyingcompounds or other entities suitable for modifying receptors and theirligands associated with chemosensory or chemosensory related sensationor reaction. In addition, there is a need in the art for compounds orother entities with such characteristics.

BRIEF SUMMARY OF THE INVENTION

The present invention is based, at least in part, on the discovery thatan extra-cellular domain, e.g., the Venus flytrap domain of achemosensory receptor, especially one or more interacting sites withinthe Venus flytrap domain, is a suitable target for compounds or otherentities to modulate the chemosensory receptor and/or its ligands.Accordingly, the present invention provides screening methods foridentifying modifiers of chemosensory receptors and their ligands aswell as modifiers capable of modulating chemosensory receptors and theirligands.

In one embodiment, the present invention provides a method of screeningfor a candidate of a chemosensory receptor ligand modifier. The methodcomprises determining whether a test entity is suitable to interact witha chemosensory receptor via an interacting site within the Venus flytrapdomain of the chemosensory receptor.

In another embodiment, the present invention provides a method ofscreening for a candidate of a chemosensory receptor ligand modifier.The method comprises determining whether a test entity is suitable tointeract with a chemosensory receptor via a first interacting sitewithin the Venus flytrap domain of the chemosensory receptor, whereinthe first interacting site is identified in light of a secondinteracting site identified based on the interaction between achemosensory receptor ligand and the chemosensory receptor.

In yet another embodiment, the present invention provides a method ofscreening for a candidate of a chemosensory receptor modifier. Themethod comprises determining whether a test entity is suitable tointeract with a chemosensory receptor via an interacting site within theVenus flytrap domain of the chemosensory receptor, wherein theinteracting site includes an interacting residue selected from the groupconsisting of N143, S144, I167, S40, S144, S165, Y103, D142, P277, K65,R383, D307, E302, D278, P185, T184, T326, E302, V384, A305, I325, I306,D307, E382, I279, I67, V66, V309, S303, T242, F103, Q328, and S168 ofT1R2 and a combination thereof, wherein a test entity suitable tointeract with the interacting site of the chemosensory receptor isindicative of a candidate of a chemosensory receptor modifier.

In yet another embodiment, the present invention provides a method ofmodulating the activity of a chemosensory receptor ligand. The methodcomprises contacting a chemosensory receptor ligand modifier with a cellcontaining T1R2 Venus flytrap domain in the presence of a chemosensoryreceptor ligand, wherein the chemosensory receptor ligand modifierinteracts with an interacting site of the chemosensory receptor.

In still another embodiment, the present invention provides achemosensory receptor ligand modifier, wherein in the presence of achemosensory receptor ligand it interacts with T1R2 Venus flytrap domainvia at least three interacting residues selected from the groupconsisting of N143, S144, I167, S40, S144, S165, Y103, D142, P277, K65,R383, D307, E302, D278, P185, T184, T326, E302, V384, A305, I325, I306,E382, I279, I67, V66, V309, S303, T242, F103, Q328, and S168 of T1R2.

In still another embodiment, the present invention provides achemosensory receptor ligand enhancer having structural Formula (I)

-   -   or a salt, hydrate, solvate or N-oxide thereof wherein:    -   G forms a single bond with either D or E and a double bond with        the other of D or E;    -   R¹ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN,        —NO₂, —OR³, —S(O)_(a)R³, —NR³R⁴, —CONR³R⁴, —CO₂R³, —NR³CO₂R⁴,        —NR³CONR⁴R⁵, —NR³CSNR⁴R⁵ or —NR³C(═NH)NR⁴R⁵, —SO₂NR²R³,        —NR²SO₂R³, —NR²SO₂NR³R⁴, —B(OR²)(OR³), —P(O)(OR²)(OR³) or        —P(O)(R²)(OR³);    -   R² is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN,        —NO₂, —OR⁶, —S(O)_(b)R⁶, —NR⁶R⁷, —CONR⁶R⁷, —CO₂R⁶, —NR⁶CO₂R⁷,        —NR⁶CONR⁷R⁸, —NR⁶CSNR⁷R⁸ or —NR⁶C(═NH)NR⁷R⁸, —SO₂NR⁵R⁶,        —NR⁵SO₂R⁶, —NR⁵SO₂NR⁶R⁷, —B(OR⁵)(OR⁶), —P(O)(OR⁵)(OR⁶),        —P(O)(R⁵)(OR⁶) or alternatively, R¹ and R² together with the        atoms to which they are bonded form an aryl, substituted aryl,        heteroaryl, substituted heteroaryl, cycloalkyl, substituted        cycloalkyl, cycloheteroalkyl or substituted cycloheteroalkyl        ring where the ring is optionally fused to another aryl,        substituted aryl, heteroaryl, substituted heteroaryl,        cycloalkyl, substituted cycloalkyl, cycloheteroalkyl or        substituted cycloheteroalkyl ring;    -   with the proviso that R¹ and R² are not both hydrogen;    -   A is hydrogen, alkyl, substituted alkyl, aryl, substituted aryl,        arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN,        —NO₂, —OR⁹, —S(O)_(c)R⁹, —NR⁹R¹⁰, —NOR⁹, —CONR⁹R¹⁰, —CO₂R⁹,        —NR⁹CO₂R¹⁰, —NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹ or —NR⁹C(═NH)NR¹⁰R¹¹;    -   B is —N— or —C(R¹²)—;    -   R¹² is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl,        —NR¹³R¹⁴, —CN, —OR¹³, —S(O)_(d)R¹³, —CO₂R¹³ or —CONR¹³R¹⁴;    -   G is —C— or —S(O)₂—;    -   provided that when G is —S(O)₂—, G forms a single bond with E;    -   D is hydrogen, alkyl, substituted alkyl, aryl, substituted aryl,        arylalkyl, substituted arylalkyl, acyl, substituted acyl, halo,        chloro, fluoro, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl, substituted        heteroarylalkyl, —OR¹⁵, —NOR¹⁵, —S(O)_(e)R¹⁵, —NR¹⁵R¹⁶, —NCN,        —CO₂R¹⁵, —CONR¹⁵R¹⁶ when the bond between D and G is a single        bond;    -   D is ═O, ═S, ═N—OR¹⁵, ═NHNHR¹⁵ when G form a double bond with D;    -   n is 0 when G is —S(O)₂— and n is 1 when G is —C—;    -   E is —NR¹⁷—, —N— or —C(R¹⁸)—;    -   provided that E is —NR¹⁷— only when G forms a single bond with        E;    -   R¹⁷ is alkyl, substituted alkyl, aryl, substituted aryl,        arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl or        —CO₂R¹⁹;    -   R¹⁸ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl,        —NR²⁰R²¹; —CN, —OR²⁰, —S(O)_(f)R²⁰, —CO₂R²⁰ or —CONR²⁰R²¹;    -   a, b, c, d, e and f are independently 0, 1 or 2; and    -   R³-R¹¹, R¹³-R¹⁶, R¹⁸, R²⁰ and R²¹ are independently hydrogen,        alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl,        substituted arylalkyl, acyl, substituted acyl, heteroalkyl,        substituted heteroalkyl, heteroaryl, substituted heteroaryl,        heteroarylalkyl or substituted heteroarylalkyl or alternatively,        R³ and R⁴, R⁴ and R⁵, R⁶ and R⁷, R⁷ and R⁸, R⁹ and R¹⁰, R¹⁰ and        R¹¹, R¹³ and R¹⁴, R¹⁵ and R¹⁶ and R²⁰ and R²¹ together with the        atoms to which they are bonded form a cycloheteroalkyl or        substituted cycloheteroalkyl ring.

In still another embodiment, the present invention provides chemosensoryreceptor ligand enhancer having structural Formula (XVI):

-   -   or a salt, solvate, hydrate or N-oxide thereof wherein:    -   each G is independently —C(R⁷⁷)(R⁷⁸)—, —C(O)—, —NR⁷⁷— or        —S(O)₂—;    -   n is 1, 2 or 3;    -   provided that when n is greater than one then only one G is        —C(O)—, —C(S), —S(O)₂— or —NR⁷⁷—;    -   Y is —C(O)—, —C(S) or —S(O)₂—;    -   R⁷⁰ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN,        —NO₂, —OR⁷², —S(O)_(a)R⁷², —NR⁷²R⁷³, —CONR⁷²R⁷³, —CO₂R⁷²,        —NR⁷²CO₂R⁷³, —NR⁷²CONR⁷³R⁷⁴, —NR⁷²CSNR⁷³R⁷⁴ or        —NR⁷²C(═NH)NR⁷³R⁷⁴, —SO₂NR⁷²R⁷³, —NR⁷²SO₂R⁷³, —NR⁷²SO₂NR⁷³R⁷⁴,        —B(OR⁷²)(OR⁷³), —P(O)(OR⁷²)(OR⁷³) or —P(O)(R⁷²)(OR⁷³);    -   R⁷¹ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN,        —NO₂, —OR⁷⁴, —S(O)_(b)R⁷⁴, —NR⁷⁴R⁷⁵, —CONR⁷⁴R⁷⁵, —CO₂R⁷⁴,        —NR⁷⁴CO₂R⁷⁵, —NR⁷⁴CONR⁷⁵R⁷⁶, —NR⁷⁴CSNR⁷⁵R⁷⁶ or        —NR⁷⁴C(═NH)NR⁷⁵R⁷⁶, —SO₂NR⁷⁴R⁷⁵, —NR⁷⁴SO₂R⁷⁵, —NR⁷⁴SO₂NR⁷⁵R⁷⁶,        —B(OR⁷⁴)(OR⁷⁵), —P(O)(OR⁷⁴)(OR⁷⁵), —P(O)(R⁷⁴)(OR⁷⁵) or        alternatively, R⁷¹ and R⁷² together with the atoms to which they        are bonded form an aryl, substituted aryl, heteroaryl,        substituted heteroaryl, cycloalkyl, substituted cycloalkyl,        cycloheteroalkyl or substituted cycloheteroalkyl ring where the        ring is optionally fused to another aryl, substituted aryl,        heteroaryl, substituted heteroaryl, cycloalkyl, substituted        cycloalkyl, cycloheteroalkyl or substituted cycloheteroalkyl        ring;    -   a and b are independently 0, 1 or 2;    -   R⁷²-R⁷⁶ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively, R⁷² and R⁷³, R⁷³        and R⁷⁴, R⁷⁴ and R⁷⁵ and R⁷⁵ and R⁷⁶ together with the atoms to        which they are bonded form a cycloheteroalkyl or substituted        cycloheteroalkyl ring; and    -   R⁷⁷-R⁷⁸ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively, R⁷⁷ and R⁷⁸,        together with the atoms to which they are bonded form a        cycloalkyl, substituted cycloalkyl, cycloheteroalkyl or        substituted cycloheteroalkyl ring.

In still another embodiment, the present invention provides chemosensoryreceptor ligand enhancer and having structural Formula (XXII):

-   -   or a salt, solvate, hydrate or N-oxide thereof wherein:    -   each G is independently —C(R⁹⁴)(R⁹⁵)—, —C(O)—, —NR⁹⁴— or        —S(O)₂—;    -   n is 1, 2 or 3;    -   provided that when n is greater than one then only one G is        —C(O)—, —S(O)₂— or —NR⁹⁴—;    -   Y is —C(O)—, —C(S)— or —S(O)₂—;    -   L is —C(R¹⁰⁴)(R¹⁰⁵)—, —O—, or —NR¹⁰⁴—;    -   R⁹² is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN,        —NO₂, —OR⁹⁸, —S(O)_(y)R⁹⁸, —NR⁹⁸R⁹⁹, —CONR⁹⁸R⁹⁹, —CO₂R⁹⁸,        —NR⁹⁸CO₂R⁹⁹, —NR⁹⁸CONR⁹⁹R¹⁰⁰, —NR⁹⁸CSNR⁹⁹R¹⁰⁰ or        —NR⁹⁸C(═NH)NR⁹⁹R¹⁰⁰, —SO₂NR⁹⁸R⁹⁹, —NR⁹⁸SO₂R⁹⁹, —NR⁹⁸SO₂NR⁹⁹R¹⁰⁰,        —B(OR⁹⁸)(OR⁹⁹), —P(O)(OR⁹⁸)(OR⁹⁹) or —P(O)(R⁹⁸)(OR⁹⁹);

R⁹³ is hydrogen, alkyl, substituted alkyl, aryl, substituted aryl,arylalkyl, substituted arylalkyl, acyl, substituted acyl, heteroalkyl,substituted heteroalkyl, heteroaryl, substituted heteroaryl,heteroarylalkyl, substituted heteroarylalkyl, —CN, —NO₂, —OR¹⁰⁰,—S(O)_(z)R¹⁰¹, —NR¹⁰¹R¹⁰², —CONR¹⁰¹R¹⁰², —CO₂R¹⁰¹, —NR¹⁰¹CO₂R¹⁰²,—NR¹⁰¹CONR¹⁰²R¹⁰³, —NR¹⁰¹CSNR¹⁰²R¹⁰³, or —NR¹⁰¹C(═NH)NR¹⁰²R¹⁰³,—SO₂NR¹⁰¹R¹⁰², —NR¹⁰¹SO₂R¹⁰², —NR¹⁰¹SO₂NR¹⁰²R¹⁰³, —B(OR¹⁰¹)(oR¹⁰²),—P(O)(OR¹⁰¹)(OR¹⁰²), —P(O)(R¹⁰¹)(OR¹⁰²) or alternatively, R⁹² and R⁹³together with the atoms to which they are bonded form an aryl,substituted aryl, heteroaryl, substituted heteroaryl, cycloalkyl,substituted cycloalkyl, cycloheteroalkyl or substituted cycloheteroalkylring where the ring is optionally fused to another aryl, substitutedaryl, heteroaryl, substituted heteroaryl, cycloalkyl, substitutedcycloalkyl, cycloheteroalkyl or substituted cycloheteroalkyl ring;

-   -   x and y are independently, 0, 1 or 2;    -   R⁹⁸-R¹⁰³ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively, R⁹⁸ and R⁹⁹, R⁹⁹        and R¹⁰⁰, R¹⁰¹ and R¹⁰² and R¹⁰¹ and R¹⁰² together with the        atoms to which they are bonded form a cycloalkyl, substituted        cycloalkyl, cycloheteroalkyl or substituted cycloheteroalkyl        ring;    -   R⁹⁴-R⁹⁵ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively, R⁹⁴ and R⁹⁵,        together with the atoms to which they are bonded form a        cycloalkyl, substituted cycloalkyl, cycloheteroalkyl or        substituted cycloheteroalkyl ring;    -   R⁹⁶ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl; and    -   R¹⁰⁴-R¹⁰⁵ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively, R¹⁰⁴ and R¹⁰⁵,        together with the atoms to which they are bonded form a        cycloalkyl, substituted cycloalkyl, cycloheteroalkyl or        substituted cycloheteroalkyl ring.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 contains exemplary human T1R1 polymorphic variations.

FIG. 2 contains exemplary human T1R2 polymorphic variations.

FIG. 3 shows the dendograms for the sequence alignments of T1R1.

FIG. 4 shows the dendograms for the sequence alignments of T1R2.

FIG. 5 shows exemplary interacting spaces for sucralose and one of thecompound of the present invention. Protein is represented as a ribbondiagram.

FIG. 6 shows exemplary interacting spaces and residues for sucralose andone of the compounds of the present invention. Protein is represented asa ribbon diagram.

FIG. 7 shows exemplary interacting spaces and residues associated withthe hinge region for sucralose and one of the compounds of the presentinvention.

FIG. 8 shows exemplary partial interacting surfaces and interactingresidues proximal to the hinge region for sucrose and sucralose.

FIG. 9 shows exemplary interacting spaces and residues associated withthe lobes for sucralose and one of the compounds of the presentinvention.

FIG. 10 shows exemplary interacting spaces and residues associated withan interacting site for sucralose and one of the compounds of thepresent invention.

FIG. 11 shows exemplary results for mapping studies using human-ratchimeric receptors.

FIG. 12 shows results for exemplary mutagenesis results.

DETAILED DESCRIPTION OF THE INVENTION

Prior to specifically describing the invention, the followingdefinitions are provided.

The term “T1R” family includes polymorphic variants, alleles, mutants,and

homologs that: (1) have about 30-40% amino acid sequence identity, morespecifically about 40, 50, 60, 70, 75, 80, 85, 90, 95, 96, 97, 98, or99% amino acid sequence identity to the T1Rs known or disclosed, e.g.,in patent application U.S. Ser. No. 10/179,373 filed on Jun. 26, 2002,Ser. No. 09/799,629 filed on Apr. 5, 2001 and U.S. Ser. No. 10/035,045filed on Jan. 3, 2002, over a window of about 25 amino acids, optimally50-100 amino acids; (2) specifically bind to antibodies raised againstan immunogen comprising an amino acid sequence selected from the groupconsisting of the T1R sequences disclosed infra, and conservativelymodified variants thereof; (3) specifically hybridize (with a size of atleast about 100, optionally at least about 500-1000 nucleotides) understringent hybridization conditions to a sequence selected from the groupconsisting of the T1R DNA sequences disclosed infra, and conservativelymodified variants thereof; (4) comprise a sequence at least about 40%identical to an amino acid sequence selected from the group consistingof the T1R amino acid sequences disclosed infra or (5) are amplified byprimers that specifically hybridize under stringent hybridizationconditions to the described T1R sequences.

In particular, these “T1Rs” include taste receptor GPCRs referred to ashT1R1, hT1R2, hT1R3, rT1R1, rT1R2, rT1R3, mT1R1, mT1R2, and mT1R3 havingthe nucleic acid sequences and amino acid sequences known or disclosed,e.g., in U.S. Ser. No. 10/179,373 filed on Jun. 26, 2002, U.S. Ser. No.09/799,629 filed on Apr. 5, 2001 and U.S. Ser. No. 10/035,045 filed onJan. 3, 2002, and variants, alleles, mutants, orthologs and chimerasthereof which specifically bind and/or respond to sweet, umami, or anyother chemosensory related ligands including activators, inhibitors andenhancers. Also T1Rs include taste receptor GPCRs expressed in humans orother mammals, e.g., cells associated with taste and/or part ofgastrointestinal system including without any limitation, esophagus,stomach, intestine (small and large), colon, liver, biliary tract,pancreas, gallbladder, etc. Also, T1R polypeptides include chimericsequences derived from portions of a particular T1R polypeptide such asT1R1, T1R2 or T1R3 of different species or by combining portions ofdifferent T1Rs wherein such chimeric T1R sequences are combined toproduce a functional sweet or umami taste receptor. For example chimericT1Rs may comprise the extracellular region of one T1R, i.e., T1R1 orT1R2 and the transmembrane region of another T1R, either T1R1 or T1R2.

Topologically, certain chemosensory GPCRs have an “N-terminal domain;”“extracellular domains,” a “transmembrane domain” comprising seventransmembrane regions, and corresponding cytoplasmic and extracellularloops, “cytoplasmic regions,” and a “C-terminal region” (see, e.g., Hoonet al., Cell 96:541-51 (1999); Buck et al., Cell 65:175-87 (1991)).These regions can be structurally identified using methods known tothose of skill in the art, such as sequence analysis programs thatidentify hydrophobic and hydrophilic domains (see, e.g., Stryer,Biochemistry, (3rd ed. 1988); see also any of a number of Internet basedsequence analysis programs, such as those found atdot.imgen.bcm.tmc.edu). These regions are useful for making chimericproteins and for in vitro assays of the invention, e.g., ligand bindingassays.

“Extracellular domains” therefore refers to the domains of chemosensoryreceptors, e.g., T1R polypeptides that protrude from the cellularmembrane and are exposed to the extracellular face of the cell. Suchregions would include the “N-terminal domain” that is exposed to theextracellular face of the cell, as well as the extracellular loops ofthe transmembrane domain that are exposed to the extracellular face ofthe cell, i.e., the extracellular loops between transmembrane regions 2and 3, transmembrane regions 4 and 5, and transmembrane regions 6 and 7.The “N-terminal domain” starts at the N-terminus and extends to a regionclose to the start of the transmembrane region. These extracellularregions are useful for in vitro ligand binding assays, both soluble andsolid phase. In addition, transmembrane regions, described below, canalso be involved in ligand binding, either in combination with theextracellular region or alone, and are therefore also useful for invitro ligand binding assays.

“Transmembrane domain,” which comprises the seven transmembrane“regions,” refers to the domains of chemosensory receptors, e.g., T1Rpolypeptides that lie within the plasma membrane, and may also includethe corresponding cytoplasmic (intracellular) and extracellular loops,also referred to as transmembrane “regions.” The seven transmembraneregions and extracellular and cytoplasmic loops can be identified usingstandard methods, as described in Kyte et al., J. Mol. Biol. 157:105-32(1982)), or in Stryer, supra.

“Cytoplasmic domains” refers to the domains of chemosensory receptors,e.g., T1R proteins that face the inside of the cell, e.g., the“C-terminal domain” and the intracellular loops of the transmembranedomain, e.g., the intracellular loops between transmembrane regions 1and 2, transmembrane regions 3 and 4, and transmembrane regions 5 and 6.“C-terminal domain” refers to the region that spans from the end of thelast transmembrane region to the C-terminus of the protein, and which isnormally located within the cytoplasm.

The term “7-transmembrane receptor” means a polypeptide belonging to asuperfamily of transmembrane proteins that have seven regions that spanthe plasma membrane seven times (thus, the seven regions are called“transmembrane” or “TM” domains TM I to TM VII).

The phrase “functional effects” or “activity” in the context of thedisclosed assays for testing compounds that modulate a chemosensoryreceptor, e.g., enhance T1R family member mediated signal transductionsuch as sweet or umami receptor functional effects or activity includesthe determination of any parameter that is indirectly or directly underthe influence of the particular chemosensory receptor, e.g., functional,physical and chemical effects. It includes, without any limitation,ligand binding, changes in ion flux, membrane potential, current flow,transcription, G protein binding, GPCR phosphorylation ordephosphorylation, signal transduction, receptor-ligand interactions,second messenger concentrations (e.g., cAMP, cGMP, IP3, or intracellularCa²⁺), in vitro, in vivo, and ex vivo and also includes otherphysiologic effects such increases or decreases of neurotransmitter orhormone release.

The term “determining the functional effect” or receptor “activity”means assays for a compound that increases or decreases a parameter thatis indirectly or directly under the influence of a chemosensoryreceptor, e.g., functional, physical and chemical effects. Suchfunctional effects can be measured by any means known to those skilledin the art, e.g., changes in spectroscopic characteristics (e.g.,fluorescence, absorbance, refractive index), hydrodynamic (e.g., shape),chromatographic, or solubility properties, patch clamping,voltage-sensitive dyes, whole cell currents, radioisotope efflux,inducible markers, oocyte chemosensory receptor, e.g., T1R geneexpression; tissue culture cell chemosensory receptor, e.g., T1Rexpression; transcriptional activation of chemosensory receptor, e.g.,T1R genes; ligand binding assays; voltage, membrane potential andconductance changes; ion flux assays; changes in intracellular secondmessengers such as cAMP, cGMP, and inositol triphosphate (IP3); changesin intracellular calcium levels; neurotransmitter release, and the like.

“Inhibitors,” “activators,” and “modifiers” of chemosensory receptor,e.g., T1R proteins are used interchangeably to refer to inhibitory,activating, or modulating molecules identified using in vitro and invivo assays for chemosensory signal transduction, e.g., ligands,agonists, antagonists, and their homologs and mimetics. Inhibitors arecompounds that, e.g., bind to, partially or totally block stimulation,decrease, prevent, delay activation, inactivate, desensitize, or downregulate taste transduction, e.g., antagonists. Activators are compoundsthat, e.g., bind to, stimulate, increase, open, activate, facilitate,enhance activation, sensitize, or up regulate chemosensory signaltransduction, e.g., agonists. Modifiers include compounds that, e.g.,alter, directly or indirectly, the activity of a receptor or theinteraction of a receptor with its ligands, e.g., receptor ligands andoptionally bind to or interact with activators or inhibitors; GProteins; kinases (e.g., homologs of rhodopsin kinase and betaadrenergic receptor kinases that are involved in deactivation anddesensitization of a receptor); and arrestins, which also deactivate anddesensitize receptors. Modifiers include genetically modified versionsof chemosensory receptors, e.g., T1R family members, e.g., with alteredactivity, as well as naturally occurring and synthetic ligands,antagonists, agonists, small chemical molecules and the like. In thepresent invention this includes, without any limitation, sweet ligands(agonists or antagonists), umami ligands (agonists and antagonists),sweet enhancers and umami enhancers and sweet taste or umami tasteinhibitors.

“Enhancer” herein refers to a compound that modulates (increases) theactivation of a particular receptor, preferably the chemosensory, e.g.,T1R2/T1R3 receptor or T1R1/T1R3 receptor but which by itself does notresult in substantial activation of the particular receptor. Herein suchenhancers will enhance the activation of a chemosensory receptor by itsligand. Typically the “enhancer” will be specific to a particularligand, i.e., it will not enhance the activation of a chemosensoryreceptor by chemosensory ligands other than the particular chemosensoryligand or ligands closely related thereto.

“Putative enhancer” herein refers to a compound identified, e.g., insilico or not, as a potential enhancer using assays which are describedherein but which enhancer activity has not yet been confirmed in vivo,e.g., in suitable taste tests.

The terms “polypeptide,” “peptide” and “protein” are usedinterchangeably herein to refer to a polymer of amino acid residues. Theterms apply to amino acid polymers in which one or more amino acidresidue is an artificial chemical mimetic of a corresponding naturallyoccurring amino acid, as well as to naturally occurring amino acidpolymers and non-naturally occurring amino acid polymer.

The “extra-cellular domain” and chemosensory receptor, e.g., T1Rreceptor regions or compositions described herein also include“analogs,” or “conservative variants” and “mimetics” (“peptidomimetics”)with structures and activity that substantially correspond to theexemplary sequences. Thus, the terms “conservative variant” or “analog”or “mimetic” refer to a polypeptide which has a modified amino acidsequence, such that the change(s) do not substantially alter thepolypeptide's (the conservative variant's) structure and/or activity, asdefined herein. These include conservatively modified variations of anamino acid sequence, i.e., amino acid substitutions, additions ordeletions of those residues that are not critical for protein activity,or substitution of amino acids with residues having similar properties(e.g., acidic, basic, positively or negatively charged, polar ornon-polar, etc.) such that the substitutions of even critical aminoacids does not substantially alter structure and/or activity.

More particularly, “conservatively modified variants” applies to bothamino acid and nucleic acid sequences. With respect to particularnucleic acid sequences, conservatively modified variants refers to thosenucleic acids which encode identical or essentially identical amino acidsequences, or where the nucleic acid does not encode an amino acidsequence, to essentially identical sequences. Because of the degeneracyof the genetic code, a large number of functionally identical nucleicacids encode any given protein.

For instance, the codons GCA, GCC, GCG and GCU all encode the amino acidalanine Thus, at every position where an alanine is specified by acodon, the codon can be altered to any of the corresponding codonsdescribed without altering the encoded polypeptide.

Such nucleic acid variations are “silent variations,” which are onespecies of conservatively modified variations. Every nucleic acidsequence herein which encodes a polypeptide also describes everypossible silent variation of the nucleic acid. One of skill willrecognize that each codon in a nucleic acid (except AUG, which isordinarily the only codon for methionine, and TGG, which is ordinarilythe only codon for tryptophan) can be modified to yield a functionallyidentical molecule. Accordingly, each silent variation of a nucleic acidwhich encodes a polypeptide is implicit in each described sequence.

Conservative substitution tables providing functionally similar aminoacids are well known in the art. For example, one exemplary guideline toselect conservative substitutions includes (original residue followed byexemplary substitution): ala/gly or ser; arg/lys; asn/gln or his;asp/glu; cys/ser; gln/asn; gly/asp; gly/ala or pro; his/asn or gln;ile/leu or val; leu/ile or val; lys/arg or gln or glu; met/leu or tyr orile; phe/met or leu or tyr; ser/thr; thr/ser; trp/tyr; tyr/trp or phe;val/ile or leu. An alternative exemplary guideline uses the followingsix groups, each containing amino acids that are conservativesubstitutions for one another: 1) Alanine (A), Serine (S), Threonine(T); 2) Aspartic acid (D), Glutamic acid (E); 3) Asparagine (N),Glutamine (Q); 4) Arginine (R), Lysine (I); 5) Isoleucine (I), Leucine(L), Methionine (M), Valine (V); and 6) Phenylalanine (F), Tyrosine (Y),Tryptophan (W); (see also, e.g., Creighton, Proteins, W. H. Freeman andCompany (1984); Schultz and Schimer, Principles of Protein Structure,Springer-Verlag (1979)). One of skill in the art will appreciate thatthe above-identified substitutions are not the only possibleconservative substitutions. For example, for some purposes, one mayregard all charged amino acids as conservative substitutions for eachother whether they are positive or negative. In addition, individualsubstitutions, deletions or additions that alter, add or delete a singleamino acid or a small percentage of amino acids in an encoded sequencecan also be considered “conservatively modified variations.”

The terms “mimetic” and “peptidomimetic” refer to a synthetic chemicalcompound that has substantially the same structural and/or functionalcharacteristics of the polypeptides, e.g., extra-cellular domain or anyregion therewith of T1R2 or T1R1. The mimetic can be either entirelycomposed of synthetic, non-natural analogs of amino acids, or may be achimeric molecule of partly natural peptide amino acids and partlynon-natural analogs of amino acids. The mimetic can also incorporate anyamount of natural amino acid conservative substitutions as long as suchsubstitutions also do not substantially alter the mimetic's structureand/or activity.

As with polypeptides of the invention which are conservative variants,routine experimentation will determine whether a mimetic is within thescope of the invention, i.e., that its structure and/or function is notsubstantially altered. Polypeptide mimetic compositions can contain anycombination of non-natural structural components, which are typicallyfrom three structural groups: a) residue linkage groups other than thenatural amide bond (“peptide bond”) linkages; b) non-natural residues inplace of naturally occurring amino acid residues; or c) residues whichinduce secondary structural mimicry, i.e., to induce or stabilize asecondary structure, e.g., a beta turn, gamma turn, beta sheet, alphahelix conformation, and the like. A polypeptide can be characterized asa mimetic when all or some of its residues are joined by chemical meansother than natural peptide bonds. Individual peptidomimetic residues canbe joined by peptide bonds, other chemical bonds or coupling means, suchas e.g., glutaraldehyde, N-hydroxysuccinimide esters, bifunctionalmaleimides, N,N′-dicyclohexylcarbodiimide (DCC) orN,N′-diisopropylcarbodiimide (DIC). Linking groups that can be analternative to the traditional amide bond (“peptide bond”) linkagesinclude, e.g., ketomethylene (e.g., —C(O)—CH₂— for —C(O)—NH—),aminomethylene —CH₂(NH)—, ethylene, olefin —CH═CH—, ether —CH₂O—,thioether —CH₂S—, tetrazole (CN₄), thiazole, retroamide, thioamide orester (see, e.g., Spatola, Chemistry and Biochemistry of Amino Acids,Peptides and Proteins, Vol. 7, 267-357, Marcell Dekker, Peptide BackboneModifications, NY (1983)). A polypeptide can also be characterized as amimetic by containing all or some non-natural residues in place ofnaturally occurring amino acid residues; non-natural residues are welldescribed in the scientific and patent literature.

“Alkyl,” by itself or as part of another substituent, refers to asaturated or unsaturated, branched, straight-chain or cyclic monovalenthydrocarbon radical derived by the removal of one hydrogen atom from asingle carbon atom of a parent alkane, alkene or alkyne. Typical alkylgroups include, but are not limited to, methyl; ethyls such as ethanyl,ethenyl, ethynyl; propyls such as propan-1-yl, propan-2-yl,cyclopropan-1-yl, prop-1-en-1-yl, prop-1-en-2-yl, prop-2-en-1-yl(allyl), cycloprop-1-en-1-yl; cycloprop-2-en-1-yl, prop-1-yn-1-yl,prop-2-yn-1-yl, etc.; butyls such as butan-1-yl, butan-2-yl,2-methyl-propan-1-yl, 2-methyl-propan-2-yl, cyclobutan-1-yl,but-1-en-1-yl, but-1-en-2-yl, 2-methyl-prop-1-en-1-yl, but-2-en-1-yl,but-2-en-2-yl, buta-1,3-dien-1-yl, buta-1,3-dien-2-yl,cyclobut-1-en-1-yl, cyclobut-1-en-3-yl, cyclobuta-1,3-dien-1-yl,but-1-yn-1-yl, but-1-yn-3-yl, but-3-yn-1-yl, etc.; and the like. Theterm “alkyl” is specifically intended to include groups having anydegree or level of saturation, i.e., groups having exclusively singlecarbon-carbon bonds, groups having one or more double carbon-carbonbonds, groups having one or more triple carbon-carbon bonds and groupshaving mixtures of single, double and triple carbon-carbon bonds. Wherea specific level of saturation is intended, the expressions “alkanyl,”“alkenyl,” and “alkynyl” are used. In some embodiments, an alkyl groupcomprises from 1 to 20 carbon atoms (C₁-C₂₀ alkyl). In otherembodiments, an alkyl group comprises from 1 to 10 carbon atoms (C₁-C₁₀alkyl). In still other embodiments, an alkyl group comprises from 1 to 6carbon atoms (C₁-C₆ alkyl).

“Alkanyl,” by itself or as part of another substituent, refers to asaturated branched, straight-chain or cyclic alkyl radical derived bythe removal of one hydrogen atom from a single carbon atom of a parentalkane. Typical alkanyl groups include, but are not limited to,methanyl; ethanyl; propanyls such as propan-1-yl, propan-2-yl(isopropyl), cyclopropan-1-yl, etc.; butanyls such as butan-1-yl,butan-2-yl (sec-butyl), 2-methyl-propan-1-yl (isobutyl),2-methyl-propan-2-yl (t-butyl), cyclobutan-1-yl, etc.; and the like.

“Alkenyl,” by itself or as part of another substituent, refers to anunsaturated branched, straight-chain or cyclic alkyl radical having atleast one carbon-carbon double bond derived by the removal of onehydrogen atom from a single carbon atom of a parent alkene. The groupmay be in either the cis or trans conformation about the double bond(s).Typical alkenyl groups include, but are not limited to, ethenyl;propenyls such as prop-1-en-1-yl, prop-1-en-2-yl, prop-2-en-1-yl(allyl), prop-2-en-2-yl, cycloprop-1-en-1-yl; cycloprop-2-en-1-yl;butenyls such as but-1-en-1-yl, but-1-en-2-yl, 2-methyl-prop-1-en-1-yl,but-2-en-1-yl, but-2-en-1-yl, but-2-en-2-yl, buta-1,3-dien-1-yl,buta-1,3-dien-2-yl, cyclobut-1-en-1-yl, cyclobut-1-en-3-yl,cyclobuta-1,3-dien-1-yl, etc.; and the like.

“Alkynyl,” by itself or as part of another substituent refers to anunsaturated branched, straight-chain or cyclic alkyl radical having atleast one carbon-carbon triple bond derived by the removal of onehydrogen atom from a single carbon atom of a parent alkyne. Typicalalkynyl groups include, but are not limited to, ethynyl; propynyls suchas prop-1-yn-1-yl, prop-2-yn-1-yl, etc.; butynyls such as but-1-yn-1-yl,but-1-yn-3-yl, but-3-yn-1-yl, etc.; and the like.

“Alkoxy,” by itself or as part of another substituent, refers to aradical of the formula —O—R¹⁹⁹, where R¹⁹⁹ is alkyl or substituted alkylas defined herein.

“Acyl” by itself or as part of another substituent refers to a radical—C(O)R²⁰⁰, where R²⁰⁰ is hydrogen, alkyl, substituted alkyl, aryl,substituted aryl, arylalkyl, substituted arylalkyl, heteroalkyl,substituted heteroalkyl, heteroarylalkyl or substituted heteroarylalkylas defined herein. Representative examples include, but are not limitedto formyl, acetyl, cyclohexylcarbonyl, cyclohexylmethylcarbonyl,benzoyl, benzylcarbonyl and the like.

“Aryl,” by itself or as part of another substituent, refers to amonovalent aromatic hydrocarbon group derived by the removal of onehydrogen atom from a single carbon atom of a parent aromatic ringsystem, as defined herein. Typical aryl groups include, but are notlimited to, groups derived from aceanthrylene, acenaphthylene,acephenanthrylene, anthracene, azulene, benzene, chrysene, coronene,fluoranthene, fluorene, hexacene, hexaphene, hexylene, as-indacene,s-indacene, indane, indene, naphthalene, octacene, octaphene, octalene,ovalene, penta-2,4-diene, pentacene, pentalene, pentaphene, perylene,phenalene, phenanthrene, picene, pleiadene, pyrene, pyranthrene,rubicene, triphenylene, trinaphthalene and the like. In someembodiments, an aryl group comprises from 6 to 20 carbon atoms (C₆-C₂₀aryl). In other embodiments, an aryl group comprises from 6 to 15 carbonatoms (C₆-C₁₅ aryl). In still other embodiments, an aryl group comprisesfrom 6 to 15 carbon atoms (C₆-C₁₀ aryl).

“Arylalkyl,” by itself or as part of another substituent, refers to anacyclic alkyl group in which one of the hydrogen atoms bonded to acarbon atom, typically a terminal or sp³ carbon atom, is replaced withan aryl group as, as defined herein. Typical arylalkyl groups include,but are not limited to, benzyl, 2-phenylethan-1-yl, 2-phenylethen-1-yl,naphthylmethyl, 2-naphthylethan-1-yl, 2-naphthylethen-1-yl,naphthobenzyl, 2-naphthophenylethan-1-yl and the like. Where specificalkyl moieties are intended, the nomenclature arylalkanyl, arylalkenyland/or arylalkynyl is used. In some embodiments, an arylalkyl group is(C₆-C₃₀) arylalkyl, e.g., the alkanyl, alkenyl or alkynyl moiety of thearylalkyl group is (C₁-C₁₀) alkyl and the aryl moiety is (C₆-C₂₀) aryl.In other embodiments, an arylalkyl group is (C₆-C₂₀) arylalkyl, e.g.,the alkanyl, alkenyl or alkynyl moiety of the arylalkyl group is (C₁-C₈)alkyl and the aryl moiety is (C₆-C₁₂) aryl. In still other embodiments,an arylalkyl group is (C₆-C₁₅) arylalkyl, e.g., the alkanyl, alkenyl oralkynyl moiety of the arylalkyl group is (C₁-C₅) alkyl and the arylmoiety is (C₆-C₁₀) aryl.

“Cycloalkyl,” by itself or as part of another substituent, refers to asaturated or unsaturated cyclic alkyl radical, as defined herein. Wherea specific level of saturation is intended, the nomenclature“cycloalkanyl” or “cycloalkenyl” is used. Typical cycloalkyl groupsinclude, but are not limited to, groups derived from cyclopropane,cyclobutane, cyclopentane, cyclohexane, and the like. In someembodiments, the cycloalkyl group comprises from 3 to 10 ring atoms(C₃-C₁₀ cycloalkyl). In other embodiments, the cycloalkyl groupcomprises from 3 to 7 ring atoms (C₃-C₇ cycloalkyl).

“Cycloheteroalkyl,” by itself or as part of another substituent, refersto a saturated or unsaturated cyclic alkyl radical in which one or morecarbon atoms (and optionally any associated hydrogen atoms) areindependently replaced with the same or different heteroatom. Typicalheteroatoms to replace the carbon atom(s) include, but are not limitedto, N, P, O, S, Si, etc. Where a specific level of saturation isintended, the nomenclature “cycloheteroalkanyl” or “cycloheteroalkenyl”is used. Typical cycloheteroalkyl groups include, but are not limitedto, groups derived from epoxides, azirines, thiiranes, imidazolidine,morpholine, piperazine, piperidine, pyrazolidine, pyrrolidone,quinuclidine, and the like. In some embodiments, the cycloheteroalkylgroup comprises from 3 to 10 ring atoms (3-10 membered cycloheteroalkyl)In other embodiments, the cycloalkyl group comprise from 5 to 7 ringatoms (5-7 membered cycloheteroalkyl). A cycloheteroalkyl group may besubstituted at a heteroatom, for example, a nitrogen atom, with a(C₁-C₆) alkyl group. As specific examples, N-methyl-imidazolidinyl,N-methyl-morpholinyl, N-methyl-piperazinyl, N-methyl-piperidinyl,N-methyl-pyrazolidinyl and N-methyl-pyrrolidinyl are included within thedefinition of “cycloheteroalkyl.” A cycloheteroalkyl group may beattached to the remainder of the molecule via a ring carbon atom or aring heteroatom.

“Compounds” refers to compounds encompassed by structural formulaedisclosed herein and includes any specific compounds within theseformulae whose structure is disclosed herein. Compounds may beidentified either by their chemical structure and/or chemical name. Whenthe chemical structure and chemical name conflict, the chemicalstructure is determinative of the identity of the compound. Thecompounds described herein may contain one or more chiral centers and/ordouble bonds and therefore, may exist as stereoisomers, such asdouble-bond isomers (i.e., geometric isomers), enantiomers ordiastereomers. Accordingly, the chemical structures depicted hereinencompass all possible enantiomers and stereoisomers of the illustratedcompounds including the stereoisomerically pure form (e.g.,geometrically pure, enantiomerically pure or diastereomerically pure)and enantiomeric and stereoisomeric mixtures. Enantiomeric andstereoisomeric mixtures can be resolved into their component enantiomersor stereoisomers using separation techniques or chiral synthesistechniques well known to the skilled artisan. The compounds may alsoexist in several tautomeric forms including the enol form, the keto formand mixtures thereof. Accordingly, the chemical structures depictedherein encompass all possible tautomeric forms of the illustratedcompounds. The compounds described also include isotopically labeledcompounds where one or more atoms have an atomic mass different from theatomic mass conventionally found in nature. Examples of isotopes thatmay be incorporated into the compounds of the invention include, but arenot limited to, ²H, ³H, ¹³C, ¹⁴C, ¹⁵N, ¹⁸O, ¹⁷O, etc. Compounds mayexist in unsolvated forms as well as solvated forms, including hydratedforms and as N-oxides. In general, compounds may be hydrated, solvatedor N-oxides. Certain compounds may exist in multiple crystalline oramorphous forms. In general, all physical forms are equivalent for theuses contemplated herein and are intended to be within the scope of thepresent invention. Further, it should be understood, when partialstructures of the compounds are illustrated, that brackets indicate thepoint of attachment of the partial structure to the rest of themolecule.

“Halo,” by itself or as part of another substituent refers to a radical—F, —Cl, —Br or —I.

“Heteroalkyl,” “Heteroalkanyl,” “Heteroalkenyl” and “Heteroalkynyl,” “bythemselves or as part of other substituents, refer to alkyl, alkanyl,alkenyl and alkynyl groups, respectively, in which one or more of thecarbon atoms (and optionally any associated hydrogen atoms), are each,independently of one another, replaced with the same or differentheteroatoms or heteroatomic groups. Typical heteroatoms or heteroatomicgroups which can replace the carbon atoms include, but are not limitedto, —O—, —S—, —N—, —Si—, —NH—, —S(O)—, —S(O)₂—, —S(O)NH—, —S(O)₂NH— andthe like and combinations thereof. The heteroatoms or heteroatomicgroups may be placed at any interior position of the alkyl, alkenyl oralkynyl groups. Typical heteroatomic groups which can be included inthese groups include, but are not limited to, —O—, —S—, —O—O—, —S—S—,—O—S—, —NR²⁰¹R²⁰²—, ═N—N═, —N═N—, —N═N—NR²⁰³R²⁰⁴, —PR²⁰⁵—, —P(O)₂,—POR²⁰⁶, —O—P(O)₂, —SO—, —SO₂—, —SnR²⁰⁷R²⁰⁸— and the like, where R²⁰¹,R²⁰², R²⁰³, R²⁰⁴, R²⁰⁵, R²⁰⁶, R²⁰⁷ and R²⁰⁸ are independently hydrogen,alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl, substitutedarylalkyl, cycloalkyl, substituted cycloalkyl, cycloheteroalkyl,substituted cycloheteroalkyl, heteroalkyl, substituted heteroalkyl,heteroaryl, substituted heteroaryl, heteroarylalkyl or substitutedheteroarylalkyl.

“Heteroaryl,” by itself or as part of another substituent, refers to amonovalent heteroaromatic radical derived by the removal of one hydrogenatom from a single atom of a parent heteroaromatic ring systems, asdefined herein. Typical heteroaryl groups include, but are not limitedto, groups derived from acridine, β-carboline, chromane, chromene,cinnoline, furan, imidazole, indazole, indole, indoline, indolizine,isobenzofuran, isochromene, isoindole, isoindoline, isoquinoline,isothiazole, isoxazole, naphthyridine, oxadiazole, oxazole, perimidine,phenanthridine, phenanthroline, phenazine, phthalazine, pteridine,purine, pyran, pyrazine, pyrazole, pyridazine, pyridine, pyrimidine,pyrrole, pyrrolizine, quinazoline, quinoline, quinolizine, quinoxaline,tetrazole, thiadiazole, thiazole, thiophene, triazole, xanthene, and thelike. In some embodiments, the heteroaryl group comprises from 5 to 20ring atoms (5-20 membered heteroaryl). In other embodiments, theheteroaryl group comprises from 5 to 10 ring atoms (5-10 memberedheteroaryl). Exemplary heteroaryl groups include those derived fromfuran, thiophene, pyrrole, benzothiophene, benzofuran, benzimidazole,indole, pyridine, pyrazole, quinoline, imidazole, oxazole, isoxazole andpyrazine.

“Heteroarylalkyl” by itself or as part of another substituent refers toan acyclic alkyl group in which one of the hydrogen atoms bonded to acarbon atom, typically a terminal or sp³ carbon atom, is replaced with aheteroaryl group. Where specific alkyl moieties are intended, thenomenclature heteroarylalkanyl, heteroarylakenyl and/orheteroarylalkynyl is used. In some embodiments, the heteroarylalkylgroup is a 6-21 membered heteroarylalkyl, e.g., the alkanyl, alkenyl oralkynyl moiety of the heteroarylalkyl is (C₁-C₆) alkyl and theheteroaryl moiety is a 5-15-membered heteroaryl. In other embodiments,the heteroarylalkyl is a 6-13 membered heteroarylalkyl, e.g., thealkanyl, alkenyl or alkynyl moiety is (C₁-C₃) alkyl and the heteroarylmoiety is a 5-10 membered heteroaryl.

“Parent Aromatic Ring System” refers to an unsaturated cyclic orpolycyclic ring system having a conjugated π electron system.Specifically included within the definition of “parent aromatic ringsystem” are fused ring systems in which one or more of the rings arearomatic and one or more of the rings are saturated or unsaturated, suchas, for example, fluorene, indane, indene, phenalene, etc. Typicalparent aromatic ring systems include, but are not limited to,aceanthrylene, acenaphthylene, acephenanthrylene, anthracene, azulene,benzene, chrysene, coronene, fluoranthene, fluorene, hexacene,hexaphene, hexylene, as-indacene, s-indacene, indane, indene,naphthalene, octacene, octaphene, octalene, ovalene, penta-2,4-diene,pentacene, pentalene, pentaphene, perylene, phenalene, phenanthrene,picene, pleiadene, pyrene, pyranthrene, rubicene, triphenylene,trinaphthalene and the like.

“Parent Heteroaromatic Ring System” refers to a parent aromatic ringsystem in which one or more carbon atoms (and optionally any associatedhydrogen atoms) are each independently replaced with the same ordifferent heteroatom. Typical heteroatoms to replace the carbon atomsinclude, but are not limited to, N, P, O, S, Si, etc. Specificallyincluded within the definition of “parent heteroaromatic ring system”are fused ring systems in which one or more of the rings are aromaticand one or more of the rings are saturated or unsaturated, such as, forexample, benzodioxan, benzofuran, chromane, chromene, indole, indoline,xanthene, etc. Typical parent heteroaromatic ring systems include, butare not limited to, arsindole, carbazole, β-carboline, chromane,chromene, cinnoline, furan, imidazole, indazole, indole, indoline,indolizine, isobenzofuran, isochromene, isoindole, isoindoline,isoquinoline, isothiazole, isoxazole, naphthyridine, oxadiazole,oxazole, perimidine, phenanthridine, phenanthroline, phenazine,phthalazine, pteridine, purine, pyran, pyrazine, pyrazole, pyridazine,pyridine, pyrimidine, pyrrole, pyrrolizine, quinazoline, quinoline,quinolizine, quinoxaline, tetrazole, thiadiazole, thiazole, thiophene,triazole, xanthene and the like.

“Patient” includes humans. The terms “human” and “patient” are usedinterchangeably herein.

“Preventing” or “prevention” refers to a reduction in risk of acquiringa disease or disorder (i.e., causing at least one of the clinicalsymptoms of the disease not to develop in a patient that may be exposedto or predisposed to the disease but does not yet experience or displaysymptoms of the disease).

“Protecting group” refers to a grouping of atoms that when attached to areactive functional group in a molecule masks, reduces or preventsreactivity of the functional group. Examples of protecting groups can befound in Green et al., “Protective Groups in Organic Chemistry”, (Wiley,2^(nd) ed. 1991) and Harrison et al., “Compendium of Synthetic OrganicMethods”, Vols. 1-8 (John Wiley and Sons, 1971-1996). Representativeamino protecting groups include, but are not limited to, formyl, acetyl,trifluoroacetyl, benzyl, benzyloxycarbonyl (“CBZ”), tert-butoxycarbonyl(“Boc”), trimethylsilyl (“TMS”), 2-trimethylsilyl-ethanesulfonyl(“SES”), trityl and substituted trityl groups, allyloxycarbonyl,9-fluorenylmethyloxycarbonyl (“FMOC”), nitro-veratryloxycarbonyl(“NVOC”) and the like. Representative hydroxy protecting groups include,but are not limited to, those where the hydroxy group is either acylatedor alkylated such as benzyl, and trityl ethers as well as alkyl ethers,tetrahydropyranyl ethers, trialkylsilyl ethers and allyl ethers.

“Salt” refers to a salt of a compound, which possesses the desiredpharmacological activity of the parent compound. Such salts include: (1)acid addition salts, formed with inorganic acids such as hydrochloricacid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, andthe like; or formed with organic acids such as acetic acid, propionicacid, hexanoic acid, cyclopentanepropionic acid, glycolic acid, pyruvicacid, lactic acid, malonic acid, succinic acid, malic acid, maleic acid,fumaric acid, tartaric acid, citric acid, benzoic acid,3-(4-hydroxybenzoyl)benzoic acid, cinnamic acid, mandelic acid,methanesulfonic acid, ethanesulfonic acid, 1,2-ethane-disulfonic acid,2-hydroxyethanesulfonic acid, benzenesulfonic acid,4-chlorobenzenesulfonic acid, 2-naphthalenesulfonic acid,4-toluenesulfonic acid, camphorsulfonic acid,4-methylbicyclo[2.2.2]-oct-2-ene-1-carboxylic acid, glucoheptonic acid,3-phenylpropionic acid, trimethylacetic acid, tertiary butylacetic acid,lauryl sulfuric acid, gluconic acid, glutamic acid, hydroxynaphthoicacid, salicylic acid, stearic acid, muconic acid, and the like; or (2)salts formed when an acidic proton present in the parent compound isreplaced by a metal ion, e.g., an alkali metal ion, an alkaline earthion, or an aluminum ion; or coordinates with an organic base such asethanolamine, diethanolamine, triethanolamine, N-methylglucamine and thelike.

“Substituted,” when used to modify a specified group or radical, meansthat one or more hydrogen atoms of the specified group or radical areeach, independently of one another, replaced with the same or differentsubstituent(s). Substituent groups useful for substituting saturatedcarbon atoms in the specified group or radical include, but are notlimited to —R^(a), halo, —O⁻, ═O, —OR^(b), —SR^(b), —S⁻, ═S,—NR^(c)R^(c), ═NR^(b), ═N—OR^(b), trihalomethyl, —CF₃, —CN, —OCN, —SCN,—NO, —NO₂, ═N₂, —N₃, —S(O)₂R^(b), —S(O)₂NR^(b), —S(O)₂O⁻, —S(O)₂OR^(b),—OS(O)₂R^(b), —OS(O)₂O⁻, —OS(O)₂OR^(b), —P(O)(O⁻)₂, —P(O)(OR^(b))(O⁻),—P(O)(OR^(b))(OR^(b)), —C(O)R^(b), —C(S)R^(b), —C(NR^(b))R^(b), —C(O)O⁻,—C(O)OR^(b), —C(S)OR^(b), —C(O)NR^(c)R^(c), —C(NR^(b))NR^(c)R^(c),—OC(O)R^(b), —OC(S)R^(b), —OC(O)O⁻, —OC(O)OR^(b), —OC(S)OR^(b),—NR^(b)C(O)R^(b), —NR^(b)C(S)R^(b), —NR^(b)C(O)O⁻, —NR^(b)C(O)OR^(b),—NR^(b)C(S)OR^(b), —NR^(b)C(O)NR^(c)R^(c), —NR^(b)C(NR^(b))R^(b) and—NR^(b)C(NR^(b))NR^(c)R^(c) where R^(a) is selected from the groupconsisting of alkyl, cycloalkyl, heteroalkyl, cycloheteroalkyl, aryl,arylalkyl, heteroaryl and heteroarylalkyl; each R^(b) is independentlyhydrogen or R^(a); and each R^(c) is independently R^(b) oralternatively, the two R^(c)s are taken together with the nitrogen atomto which they are bonded form a 4-, 5-, 6- or 7-memberedcycloheteroalkyl which may optionally include from 1 to 4 of the same ordifferent additional heteroatoms selected from the group consisting ofO, N and S. As specific examples, —NR^(c)R^(c) is meant to include —NH₂,—NH-alkyl, N-pyrrolidinyl and N-morpholinyl.

Similarly, substituent groups useful for substituting unsaturated carbonatoms in the specified group or radical include, but are not limited to,—R^(a), halo, —O⁻, —OR⁻, —SR⁻, —S⁻, —NR^(c)R^(c), trihalomethyl, —CF₃,—CN, —OCN, —SCN, —NO, —NO₂, —N₃, —S(O)₂R^(b), —S(O)₂O⁻, —S(O)₂OR^(b),—OS(O)₂R^(b), —OS(O)₂O⁻, —OS(O)₂OR^(b), —P(O)(O⁻)₂, —P(O)(OR^(b))(O⁻),—P(O)(OR^(b))(OR^(b)), —C(O)R^(b), —C(S)R^(b), —C(NR^(b))R^(b), —C(O)O⁻,—C(O)OR^(b), —C(S)OR^(b), —C(O)NR^(c)R^(c), —C(NR^(b))NR^(c)R^(c),—OC(O)R^(b), —OC(S)R^(b), —OC(O)O⁻, —OC(O)OR^(b), —OC(S)OR^(b),—NR^(b)C(O)R^(b), —NR^(b)C(S)R^(b), —NR^(b)C(O)O⁻, —NR^(b)C(O)OR^(b),—NR^(b)C(S)OR^(b), —NR^(b)C(O)NR^(c)R^(c), —NR^(b)C(NR^(b))R^(b) and—NR^(b)C(NR^(b))NR^(c)R^(c), where R^(a), R^(b) and R^(c) are aspreviously defined.

Substituent groups useful for substituting nitrogen atoms in heteroalkyland cycloheteroalkyl groups include, but are not limited to, —R^(a),—O⁻, —OR^(b), —SR^(b), —S⁻, —NR^(c)R^(c), trihalomethyl, —CF₃, —CN, —NO,—NO₂, —S(O)₂R^(b), —S(O)₂O⁻, —S(O)₂OR^(b), —OS(O)₂R^(b), —OS(O)₂O⁻,—OS(O)₂OR^(b), —P(O)(O⁻)₂, —P(O)(OR^(b))(O⁻), —P(O)(OR^(b))(OR^(b)),—C(O)R^(b), —C(S)R^(b), —C(NR^(b))R^(b), —C(O)OR^(b), —C(S)OR^(b),—C(O)NR^(c)R^(c), —C(NR^(b))NR^(c)R^(c), —OC(O)R^(b), —OC(S)R^(b),—OC(O)OR^(b), —OC(S)OR^(b), —NR^(b)C(O)R^(b), —NR^(b)C(S)R^(b),—NR^(b)C(O)OR^(b), —NR^(b)C(S)OR^(b), —NR^(b)C(O)NR^(c)R^(c),—NR^(b)C(NR^(b))R^(b) and —NR^(b)C(NR^(b))NR^(c)R^(c) where R^(a), R^(b)and R^(c) are as previously defined.

Substituent groups from the above lists useful for substituting otherspecified groups or atoms will be apparent to those of skill in the art.

The substituents used to substitute a specified group can be furthersubstituted, typically with one or more of the same or different groupsselected from the various groups specified above.

“Treating” or “treatment” of any disease or disorder refers, in someembodiments, to ameliorating the disease or disorder (i.e., arresting orreducing the development of the disease or at least one of the clinicalsymptoms thereof). In other embodiments “treating” or “treatment” refersto ameliorating at least one physical parameter, which may not bediscernible by the patient. In yet other embodiments, “treating” or“treatment” refers to inhibiting the disease or disorder, eitherphysically, (e.g., stabilization of a discernible symptom),physiologically, (e.g., stabilization of a physical parameter) or both.In yet other embodiments, “treating” or “treatment” refers to delayingthe onset of the disease or disorder.

“Therapeutically effective amount” means the amount of a compound that,when administered to a patient for treating a disease, is sufficient toeffect such treatment for the disease. The “therapeutically effectiveamount” will vary depending on the compound, the disease and itsseverity and the age, weight, etc., of the patient to be treated.

“Vehicle” refers to a diluent, adjuvant, excipient or carrier with whicha compound is administered.

The present invention is based, at least in part, on the discovery thatan extra-cellular domain, e.g., the Venus flytrap domain of achemosensory receptor, especially one or more interacting sites withinthe Venus flytrap domain, is a suitable target for compounds or otherentities to modulate the chemosensory receptor and/or its ligands.Accordingly, the present invention provides screening methods foridentifying chemosensory receptor modifiers as well as chemosensoryreceptor ligand modifiers. In addition, the present invention providescompounds and compositions capable of modulating chemosensory receptorsas well as chemosensory receptor ligands.

According to one aspect of the present invention, it provides methods ofscreening for chemosensory receptor modifiers by determining whether atest entity is suitable to interact with a chemosensory receptor via oneor more interacting sites within the extra-cellular domain of thechemosensory receptor, e.g., the Venus flytrap domain of thechemosensory receptor. According to another aspect of the presentinvention, it provides methods of screening for chemosensory receptorligand modifiers by determining whether a test entity is suitable tointeract with a chemosensory receptor, and optionally its ligand via oneor more interacting sites within the extra-cellular domain, e.g., theVenus flytrap domain of the chemosensory receptor, optionally in thepresence of a chemosensory receptor ligand.

In general, the extra-cellular domain of a chemosensory receptor refersto the extra-cellular amino-terminus of a chemosensory receptor andusually includes a ligand-binding domain and a cysteine-rich linkerdomain, which connects the ligand-binding domain and the rest of theprotein. In Class C GPCRs, the ligand binding domain is generallyreferred to as a Venus flytrap domain, the structure of which has beenelucidated, e.g., using X-ray crystallography.

A Venus flytrap domain typically consists of two relatively rigid lobesconnected by three strands forming a flexible “hinge” region. In theabsence of a ligand, the Venus flytrap domain tends to adopt openconformations with well-separated lobes as well as closed conformationswith lobes closer together. In one example, the Venus flytrap domainincludes a region from amino acid 36 to amino acid 509 of human T1R1,amino acid 31 to amino acid 507 of human T1R2, and/or amino acid 35 toamino acid 511 of human T1R3.

The Venus flytrap domain of the present invention includes any ligandbinding domain or ligand interacting domain within the extra-cellulardomain of a chemosensory receptor. In one embodiment, the Venus flytrapdomain of the present invention includes any ligand binding domain of amember of the T1R family. In another embodiment, the Venus flytrapdomain of the present invention includes any extra-cellular domain of achemosensory receptor with a structure comprising two lobes connected bya hinge region. In yet another embodiment, the Venus flytrap domain ofthe present invention includes any domain corresponding to the structureand/or function of a region including amino acid 36 to amino acid 509 ofhuman T1R1, amino acid 31 to amino acid 507 of human T1R2, and/or aminoacid 35 to amino acid 511 of human T1R3. In still another embodiment,the Venus flytrap domain of the present invention includes any ligandbinding domain of T1R1, T1R2, and/or T1R3 as well as any polymorphicvariation, allele, or mutation thereof. Exemplary illustrations ofpolymorphic variations for T1R1 and T1R2 are shown in FIGS. 1-4.

According to the present invention, a chemosensory receptor can be anyreceptor associated with chemosensory sensation or chemosensory ligandtriggered signal transduction, e.g., via taste receptors or tasterelated receptors expressed in taste bud, gastrointestinal tract, etc.In one embodiment, a chemosensory receptor is a receptor that belongs tothe 7-transmembrane receptor superfamily or G protein-coupled receptors(GPCRs). In another embodiment, a chemosensory receptor is a receptorcarrying out signal transduction via one or more G proteins. In yetanother embodiment, a chemosensory receptor is a receptor that belongsto family C or class C of GPCRs. In yet another embodiment, achemosensory receptor is a receptor that belongs to the T1R family. Inyet another embodiment, a chemosensory receptor is a receptor of T1R1,T1R2, T1R3, or their equivalences or variances or a combination thereof.In still another embodiment, a chemosensory receptor is a hetero-dimerof T1R2 and T1R3, or their equivalences or variances.

According to the present invention, an interacting site within the Venusflytrap domain of a chemosensory receptor can be one or more interactingresidues or a three dimensional interacting space or a combinationthereof. In one embodiment, the interacting site of the presentinvention is within the Venus flytrap domain of T1R2. In anotherembodiment, the interacting site of the present invention is within theVenus flytrap domain of T1R3. In yet another embodiment, the interactingsite of the present invention is within the Venus flytrap domain of bothT1R2 and T1R3.

Usually such an interacting site can be determined by any suitable meansknown or later discovered in the art. For example, such interacting sitecan be determined based on computer modeling, e.g., using software suchas Homology or Modeller (by Accelrys Corporation) to construct threedimensional homology models of a chemosensory receptor Venus flytrapdomain, e.g., the T1R2 and/or T1R3 Venus flytrap domains based oncrystal structures of homologous Venus flytrap domains.

Such an interacting site can also be determined, e.g., based on X-raycrystallography and the three dimensional structure of a chemosensoryreceptor determined therefrom, e.g., the T1R2, T1R3, or T1R2/T1R3heterodimer. Alternatively, for example, such an interacting site can bedetermined based on molecular mechanical techniques, e.g., normal modeanalysis, loop generation techniques, Monte Carlo and/or moleculardynamics simulations to explore motions and alternative conformations ofthe Venus flytrap domains, docking simulations to dock candidatereceptor ligands and candidate receptor ligand modifiers into thesemodels or into experimentally determined structures of chemosensoryreceptors, e.g., T1R1 and T1R2.

In addition, for example, such an interacting site can be determinedbased on mutagenesis, e.g., site-directed mutagenesis or a combinationof two or more suitable methods known or later discovered, e.g., methodsdescribed herein.

In one example, such an interacting site is located in part of achemosensory receptor, e.g., T1R2 and can be determined in the presenceor absence of the other part of the chemosensory receptor, e.g., T1R3.In another example, such an interacting site can be determined in thepresence or absence of a chemosensory receptor modifier and/orchemosensory receptor ligand modifier.

In one embodiment, the interacting site within the Venus flytrap domainof a chemosensory receptor includes one or more interacting residues ofthe Venus flytrap domain of a chemosensory receptor. According to thepresent invention, the interacting residue of the Venus flytrap domainof a chemosensory receptor is a residue associated with any direct orindirect interaction between a chemosensory receptor and a chemosensoryreceptor modifier or a chemosensory receptor ligand modifier or both.

In one example, the interacting residue of the present inventionincludes any residue of a chemosensory receptor associated with aninteraction between a chemosensory receptor modifier and a chemosensoryreceptor. In another example, the interacting residue of the presentinvention includes any residue of a chemosensory receptor associatedwith an interaction between a chemosensory receptor ligand modifier anda chemosensory receptor. In yet another example, the interacting residueof the present invention includes any residue of a chemosensory receptorassociated with an interaction between a chemosensory receptor, achemosensory receptor modifier and a chemosensory receptor ligandmodifier.

In still another example, the interacting residue of the presentinvention includes any residue of a chemosensory receptor associatedwith an interaction between a chemosensory receptor and a sweet flavorentity, e.g. any natural or synthesized sweet flavor compound including,without any limitation, non-caloric sweet flavor compounds, reducedcaloric sweet flavor compounds, non-target caloric sweet flavorcompounds, etc. Exemplary sweet flavor compounds include, without anylimitation, cyclamic acid, mogroside, tagatose, maltose, galactose,mannose, sucrose, fructose, lactose, aspartame, neotame and otheraspartame derivatives, saccharin, sucralose, acesulfame K, glucose,erythritol, D-tryptophan, glycine, mannitol, sorbitol, maltitol,lactitol, isomalt, hydroganeted glucose syrup (HGS), hydrogenated starchhydrolyzate (HSH), stevioside, rebaudioside A and other sweetStevia-based glycosides, alitame, carrelame and other guanidine-basedsweeteners, tagatose, xylitol, high fructose corn syrup, etc.

In still another example, the interacting residue of the presentinvention includes any residue of a chemosensory receptor associatedwith an interaction between a chemosensory receptor and a sweet flavorentity enhancer. In still another example, the interacting residue ofthe present invention includes any residue of a chemosensory receptorassociated with an interaction between a chemosensory receptor, a sweetflavor entity, and a sweet flavor entity enhancer.

In another instance, the interacting residue of the present invention isa residue within the Venus flytrap domain of a chemosensory receptor,wherein any mutation of which could result in a change of the activityof the chemosensory receptor or the impact of a chemosensory receptorligand to the chemosensory receptor or both. For example, theinteracting residue of the present invention can include any residuewithin the Venus flytrap domain of a chemosensory receptor, wherein themutation of which results in a detectable change, e.g., qualitative orquantitative change of the activity of the chemosensory receptor inresponse to a chemosensory receptor modifier and/or chemosensoryreceptor ligand modifier.

In yet another instance, the interacting residue of the presentinvention is a residue within the Venus flytrap domain of a chemosensoryreceptor that interacts or forms productive interaction(s), e.g., vander Waals, burial of hydrophobic atoms or atomic groups, hydrogen bonds,ring stacking interactions, or salt-bridging electrostatic interactionswith a chemosensory receptor modifier or chemosensory receptor ligandmodifier, or both.

In still another instance, the interacting residue of the Venus flytrapdomain of a chemosensory receptor can be any residue constituting one ormore interacting structural components of the Venus flytrap domain,which are associated, directly or indirectly, with the interactionbetween a chemosensory receptor and a chemosensory receptor modifier ora chemosensory receptor ligand modifier or both. For example, the Venusflytrap domain structure of a chemosensory receptor generally includestwo lobes joint by a hinge region. Residues constituting an interactingstructural component of the Venus flytrap domain can be, e.g., residuesconstituting the hinge region, the inner side of each lobe, or residueson each lobe that are brought into close proximity during activation orconformational change of the Venus flytrap domain, including without anylimitation, residues on the inner surfaces of the lobes pointing towardseach other or on the tips of the lobes where the residues are partiallyexposed to solvent but still close to residues on the opposite lobe,etc.

Exemplary interacting residues of the Venus flytrap domain of achemosensory receptor include any one or more residues of 1) N143, S144,and I167 of a human T1R2, 2) S40, S144, S165, Y103, D142, and P277 of ahuman T1R2, 3) K65, R383, D307, E302, and D278 of a human T1R2, 4) I167,P185, T184, T326, E302, V384, A305, I325, I306, R383, D307, E382, D278,I279, I67, V66, V309, D142, S165, S40, S303, T242, F103, Q328, and S168of a human T1R2, 5) N143, S144, I167, K65, R383, D307, E302, D278, P185,T184, T326, E302, V384, A305, I325, I306, D307, E382, I279, I67, V66,V309, D142, S165, S40, S303, T242, F103, Q328, and S168 of a human T1R2,and 6) N143, I167, K65, R383, D307, E302, D278, P185, T184, T326, V384,A305, I325, I306, D307, E382, I279, I67, V66, V309, D142, S165, S40,S303, T242, F103, Q328, and S168 of a human T1R2.

Exemplary interacting residues of the Venus flytrap domain of achemosensory receptor with respect to a chemosensory receptor modifierinclude one or more residues of 1) N143, S144, and I167 of a human T1R2,2) S40, S144, S165, Y103, D142, and P277 of a human T1R2, 3) I167, P185,T184, T326, E302, V384, A305, I325, I306, R383, D307, E382, D278, I279,I67, V66, V309, D142, S165, S40, S303, T242, F103, Q328, and S168 of ahuman T1R2, 4) N143 and I167 of a human T1R2, 5) S40, S165, Y103, D142,and P277 of a human T1R2, and 6) I167, P185, T184, T326, V384, A305,I325, I306, R383, D307, E382, D278, I279, I67, V66, V309, D142, S165,S40, S303, T242, F103, Q328, and S168 of a human T1R2.

Exemplary interacting residues of the Venus flytrap domain of achemosensory receptor with respect to a sweet flavor entity such assucrose and sucralose include one or more residues of S40, S144, Y103,D142, P277 of a human T1R2. Exemplary interacting residues of the Venusflytrap domain of a chemosensory receptor with respect to a sweet flavorentity such as saccharin or acesulfame K include one or more residues ofK65, R383, D307, E302, and D278 of a human T1R2.

Exemplary interacting residues of the Venus flytrap domain of achemosensory receptor with respect to a chemosensory receptor ligandmodifier, e.g., chemosensory receptor ligand enhancer include one ormore residues of 1) K65, R383, D307, E302, and D278 of a human T1R2, 2)S40, S144, S165, Y103, D142, and P277 of a human T1R2, and 3) I167,P185, T184, T326, E302, V384, A305, I325, I306, R383, D307, E382, D278,I279, I67, V66, V309, D142, S165, S40, S303, T242, F103, Q328, and S168of a human T1R2.

In the context of the present invention, any reference to a particularinteracting residue, e.g., N143 of a human T1R2 receptor, includes allof its corresponding residues, e.g., 1) any residue of a human ornon-human T1R2 that corresponds to the same position in any method ofsequence alignment, 2) any residue of a human or non-human T1R2 thatcorresponds to the same position in any method of computer modeling inthe presence or absence of a ligand or ligand modifier, 3) any residueof a human or non-human T1R2 that corresponds to the structural orfunctional role of the particular interacting residue, 4) any residue ofa human or non-human T1R2 that is a polymorphic variation, alleles,mutation, etc. of the particular residue, 5) any residue of a human ornon-human T1R2 that is a conservative substitution or conservativelymodified variant of the particular residue, and 6) any correspondingresidue of a human or non-human T1R2 in its modified form, e.g.,artificial chemical mimetic of the particular interacting residue orun-modified form, e.g., naturally occurring form.

In another embodiment, the interacting site within the Venus flytrapdomain of a chemosensory receptor is a three dimensional interactingspace within the Venus flytrap domain outlined or defined, partially orentirely, by interacting residues or one or more interfaces, e.g.,interacting points, lines or surfaces between a chemosensory receptorand one or more chemosensory receptor modifiers or chemosensory receptorligand modifiers or a combination thereof. According to the presentinvention, a residue outlining or lining a space includes any residuehaving one or more backbones and/or side-chain atoms that are positionedso that they can potentially interact with atoms of a chemosensoryreceptor ligand or chemosensory receptor ligand modifier or both.

For example, the interacting space of the present invention can be anypartial or whole space within the Venus flytrap domain that is usuallyoccupied by one or more chemosensory receptor modifiers or chemosensoryreceptor ligand modifiers when they interact with a chemosensoryreceptor individually or together. In one example, the interacting spaceof the present invention is a space within the Venus flytrap domainusually occupied by a chemosensory receptor modifier, e.g., sweet flavorentity. In another example, the interacting space of the presentinvention is a space within the Venus flytrap domain usually occupied bya chemosensory receptor ligand modifier, e.g., sweet flavor enhancer inthe presence of a chemosensory receptor ligand. In yet another example,the interacting space of the present invention is a space within theVenus flytrap domain usually occupied by a chemosensory receptormodifier, e.g., sweet flavor entity and a chemosensory receptor ligandmodifier, e.g., sweet flavor entity enhancer. In still another example,the interacting space of the present invention is a space within theVenus flytrap domain that is defined, shaped, or transformed into basedon an interaction between a chemosensory receptor and its ligand or itsligand modifier occurred partially or entirely outside of the space.

According to the present invention, the Venus flytrap domain of achemosensory receptor can be generally viewed as two lobes joined by ahinge region. Exemplary interacting space within the Venus flytrapdomain of a chemosensory receptor includes any space associated with thehinge region, the inner side of one or two lobes, the tip of one or twolobes or a combination thereof of a chemosensory receptor.

Exemplary interacting space within the Venus flytrap domain of achemosensory receptor with respect to a chemosensory receptor modifierincludes any space within the Venus flytrap domain outlined or at leastpartially defined by the hinge region. According to the presentinvention, the hinge region usually comprises residues that are close tothe three strands connecting the two lobes. In one example, the hingeregion comprises residues that are homologous to residues observedcoordinating agonists and antagonists in crystal structures of one ormore Venus flytrap domains such as that of the mGluR receptor. Inanother example, the hinge region of T1R2 includes residues N143, S144,and I167 of T1R2.

Exemplary interacting sites within the Venus flytrap domain of achemosensory receptor with respect to a chemosensory receptor ligandmodifier include any space outlined or at least partially defined by theinner side of one or two lobes away from the hinge region, as well asresidues on the tips of the lobes that are brought into close proximityto residues on the other lobe.

In yet another embodiment, the interacting site within the Venus flytrapdomain of a chemosensory receptor is a combination of one or moreinteracting residues with an interacting space of the chemosensoryreceptor. For example, the interacting site of a chemosensory receptorcan be interacting residues associated with one interacting structuralcomponent of a chemosensory receptor in combination with a threedimensional space adjacent, e.g., not less than 1 Angstrom and not morethan 30 Angstroms, to that interacting structural component. Anotherexample of the interacting site of a chemosensory receptor includesinteracting residues associated with one interacting structuralcomponent of a chemosensory receptor in combination with a threedimensional space apart from the interacting structural component.

In general, the screening methods provided by the present invention canbe carried out by any suitable means known or later discovered. In oneembodiment, the screening methods provided by the present invention arecarried out in silico, e.g., via “virtue screening” using any suitablecomputer modeling system or via specific or rational design of acompound using any suitable computer design system.

In another embodiment, the screening methods provided by the presentinvention are carried out via biological assays, e.g., high throughputscreening of interactions between compounds and a chemosensory receptoror its fragments, e.g., genetically modified chemosensory receptors orfragments thereof such as mutated Venus flytrap domains of chemosensoryreceptors. In yet another embodiment, the screening methods provided bythe present invention are carried out via a combination of biologicalassay(s) and computer modeling and/or design. For example, the screeningmethods provided by the present invention can be a combination ofhigh-throughput screening of interactions between computer designed orpre-screened compounds and mutated Venus flytrap domains of chemosensoryreceptors.

In one example, the screening method provided by the present inventionfor chemosensory receptor modifiers includes determining an interactingsite using a known chemosensory receptor modifier, e.g., structurallysimilar to a chemosensory receptor modifier of interest and thendetermining whether a test entity is suitable to interact with thechemosensory receptor via the interacting site so determined.

In another example, the screening method provided by the presentinvention for chemosensory receptor modifiers includes determiningwhether a test entity is suitable to interact with a chemosensoryreceptor via a predetermined interacting site, e.g., an interacting siteselected or determined prior to screening, including without anylimitation, selected or determined based on known chemosensory receptormodifiers or desired characteristics of a chemosensory receptormodifiers.

In yet another example, the screening method provided by the presentinvention for chemosensory receptor ligand modifiers includesdetermining a docking site for a chemosensory receptor ligand andsubsequently determining whether a test entity is suitable to interactwith the chemosensory receptor ligand via an interacting site selectedin light of the docking of the chemosensory receptor ligand. Accordingto the present invention, docking process can include any known or laterdiscovered methods. For instance, docking can be a process in which thecenter of mass, orientations, and internal degrees of freedom of amolecule are modified to fit them into a predetermined space in astructural model. In one example, docking can be a process whichincludes translating and rotating a chemosensory receptor ligandrelative to the chemosensory receptor structural model, e.g., the Venusflytrap domain of a chemosensory receptor model while simultaneouslyadjusting internal torsional angles of the chemosensory receptor ligandto fit it into the interacting site of the chemosensory receptor. Anexample of a widely used docking program is GLIDE from Schroedinger,Inc.

In yet another example, the screening method provided by the presentinvention for chemosensory receptor ligand modifiers includesdetermining a docking site for a chemosensory receptor ligand andsubsequently determining an interacting site using a known modifier ofthe chemosensory receptor ligand and then determining whether a testentity is suitable to interact with the chemosensory receptor ligand viathe interacting site so determined.

In yet another example, the screening method provided by the presentinvention for chemosensory receptor ligand modifiers includesdetermining whether a test entity is suitable to interact with achemosensory receptor via a predetermined interacting site forchemosensory receptor ligand modifiers.

In still another example, the screening method provided by the presentinvention for chemosensory receptor ligand modifiers includesdetermining whether a test entity is suitable to interact with achemosensory receptor by determining, e.g., concurrently whether achemosensory receptor ligand and the test entity are suitable tointeract with the chemosensory receptor in a predetermined interactingsite of the chemosensory receptor or an interacting site determinedusing known chemosensory receptor ligand and its modifier of interest.

In still another example, the screening method provided by the presentinvention for chemosensory receptor ligand modifiers includesdetermining whether a test entity is suitable to interact with achemosensory receptor via an interacting site, either pre-determined ornot, as well as whether a test entity is suitable to interact with achemosensory receptor ligand.

In still another example, the screening method provided by the presentinvention for chemosensory receptor ligand modifiers includesdetermining whether a test entity is suitable to interact with achemosensory receptor via an interacting site, either pre-determined ornot, as well as whether such interaction can stabilize a conformation,e.g., a semi-closed or closed conformation within the Venus flytrapdomain formed by the interaction between a chemosensory receptor ligandand a chemosensory receptor, e.g., by forming productive additionalinteractions within the hinge region, lobes of the Venus flytrap domain,or tips of the flytrap domain via van der Waals, burial of hydrophobicatoms or atomic groups, hydrogen bonds, ring stacking interactions, orsalt-bridging electrostatic interactions, etc.

In general, any suitable means known or later discovered can be used todetermine whether a test entity is suitable to interact with aninteracting site of the present invention. For example, one coulddetermine the suitability of a test entity based on whether part or allof a test entity fits into a particular space entailed by an interactingsite, e.g., whether a test entity fits into a particular space entailedby an interacting site substantially the same way a known chemosensoryreceptor modifier or chemosensory receptor ligand modifier does.

Alternatively one could determine the suitability of a test entity withrespect to an interacting site based on whether it forms interactionswith a chemosensory receptor similar to the interactions formed by aknown chemosensory receptor modifier or chemosensory receptor ligandmodifier when they interact with the interacting site.

In addition, one could determine the suitability of a test entity basedon whether it forms productive interactions with an interacting site,e.g., van der Waals, burial of hydrophobic atoms or atomic groups,hydrogen bonds, ring stacking interactions, or salt-bridgingelectrostatic interactions, etc. In one embodiment, one could determinethe suitability of a test entity being a chemosensory receptor ligandmodifier based on whether it forms productive interactions with aninteracting site without forming van der Waals overlapping with one ormore atoms of a chemosensory receptor or the chemosensory receptorligand, e.g., in the context of one or more conformations of the Venusflytrap domain in light of the possible flexibility of the Venus flytrapdomain.

According to the present invention, a test entity suitable to interactwith one or more interacting sites within the Venus flytrap domain of achemosensory receptor is indicative of a candidate for a chemosensoryreceptor modifier or chemosensory receptor ligand modifier. In oneembodiment, a test entity suitable to interact with one or moreinteracting sites within the Venus flytrap domain of T1R2 is indicativeof a candidate for a T1R2 receptor modifier or T1R2 receptor ligandmodifier. In another embodiment, a test entity suitable to interact withone or more interacting sites within the Venus flytrap domain of T1R2 isindicative of a candidate for a T1R receptor modifier or T1R receptorligand modifier. In yet another embodiment, a test entity suitable tointeract with one or more interacting sites within the Venus flytrapdomain of T1R2 is indicative of a candidate for a receptor modifier orreceptor ligand modifier for a receptor of GPCR superfamily. In stillanother embodiment, a test entity suitable to interact with one or moreinteraction sites within the Venus flytrap domain of a chemosensoryreceptor is indicative of a candidate for a receptor modifier orreceptor ligand modifier of a receptor that corresponds to thechemosensory receptor or belongs to the same family or class as of thechemosensory receptor.

According to the present invention, a test entity suitable to interactwith one or more interacting sites within the Venus flytrap domain of achemosensory receptor is indicative of a candidate for a chemosensoryreceptor modifier or chemosensory receptor ligand modifier. In oneembodiment, a test entity suitable to interact with one or moreinteracting sites within the Venus flytrap domain of T1R2 is indicativeof a candidate for a T1R2 receptor modifier or T1R2 receptor ligandmodifier.

In one example, a test entity suitable to interact with one or moreinteracting sites containing one or more interacting residues of K65,D278, L279, D307, R383, and V384 of human T1R2 is indicative of acandidate for a T1R2 receptor ligand enhancer.

In another example, a test entity suitable to interact with one or moreinteracting sites containing one or more interacting residues of S40,S144, Y103, D142, and P277 of human T1R2 is indicative of a candidatefor a T1R2 receptor ligand enhancer with respect to sucrose or sucraloseor any ligand with a structure similar to sucrose or sucralose or anyligand interacting with T1R2 in a way similar to that of sucrose orsucralose, e.g., via one or more interacting spaces and/or residues usedby sucrose or sucralose.

In the context of the present application, any reference to a modifier,e.g. enhancer or inhibitor of a T1R2 receptor or T1R2 receptor ligandincludes a modifier for any T1R receptor, any receptor of GPCRsuper-family, or any receptor corresponding to T1R2 receptor, e.g., anyreceptor with a structure, function, or expression pattern overlappingor similar to that of T1R2. In the present invention, a test entity canbe any compound or molecule, e.g., any compound or entity thatpotentially could be a source for a desired chemosensory receptormodifier or chemosensory receptor ligand modifier. For example, a testentity can be a member of a combinatorial library, a member of a naturalcompound library, a “specifically designed” compound that is designedbased on various desirable features or rationales, etc.

In general, a chemosensory receptor modifier or ligand includes anycompound or entity capable of interacting with, e.g., binding to achemosensory receptor or modulating the structure or function of achemosensory receptor, e.g., activate, deactivate, increase, or decreasethe signal transduction activity of a chemosensory receptor, especiallyvia G-protein signal transduction pathway.

In one embodiment, a chemosensory receptor modifier or ligand is acompound or entity with sweet flavor including without any limitationany natural or synthesized sweet flavor compound, e.g., non-caloricsweet flavor compounds, reduced caloric sweet flavor compounds,non-target caloric sweet flavor compounds, etc. Exemplary sweet flavorcompounds include, without any limitation, cyclamic acid, mogroside,tagatose, maltose, galactose, mannose, sucrose, fructose, lactose,aspartame, neotame and other aspartame derivatives, saccharin,sucralose, acesulfame K, glucose, erythritol, D-tryptophan, glycine,mannitol, sorbitol, maltitol, lactitol, isomalt, hydroganeted glucosesyrup (HGS), hydrogenated starch hydrolyzate (HSH), stevioside,rebaudioside A and other sweet Stevia-based glycosides, alitame,carrelame and other guanidine-based sweeteners, tagatose, xylitol, highfructose corn syrup, etc.

In another embodiment, a chemosensory receptor modifier or ligand (usedinterchangeably in the present invention) is a compound or entitycapable of activating a chemosensory receptor, e.g., activating theG-protein signal transduction pathway associated with the chemosensoryreceptor. In yet another embodiment, a chemosensory receptor modifier orligand is a compound or entity capable of blocking or decreasing theactivation of a chemosensory receptor. In still another embodiment, achemosensory receptor modifier or ligand is a compound or entity capableof modulating the activity of a chemosensory receptor and inducing atherapeutically desirable reaction or signal transduction. In stillanother embodiment, a chemosensory receptor modifier or ligand is achemosensory receptor ligand modifier.

According to the present invention, a chemosensory receptor ligandmodifier includes any compound or entity capable of interacting ormodulating the activity of a chemosensory receptor modifier or theactivity of a chemosensory receptor in the presence of a chemosensoryreceptor modifier. In one embodiment, a chemosensory receptor ligandmodifier is an enhancer of a chemosensory receptor modifier. In anotherembodiment, a chemosensory receptor ligand modifier is an antagonist ofa chemosensory receptor modifier. In yet another embodiment, achemosensory receptor ligand modifier is an enhancer of a chemosensoryreceptor modifier without having substantial activity of thechemosensory receptor modifier. In still another embodiment, achemosensory receptor ligand modifier is an enhancer of a sweet flavoredcompound without having substantial sweet flavor by itself, e.g., asjudged by animals or humans such as majority of a panel of at leasteight human taste testers, via procedures commonly known in the field.In still yet another embodiment, a chemosensory receptor ligand modifieris an enhancer or inhibitor of a chemosensory receptor modifier andcapable of inducing a desirable therapeutic reaction or signaltransduction.

According to another aspect of the present invention, it provideschemosensory receptor ligand modifiers. In one embodiment, it provideschemosensory receptor ligand modifiers identified by the screen methodsof the present invention. In another embodiment, it provideschemosensory receptor ligand modifiers capable of interacting with achemosensory receptor via an interacting site of the present invention.In yet another embodiment, it provides chemosensory receptor ligandmodifiers capable of interacting with a chemosensory receptor via one ormore interacting residues of the chemosensory receptor. In still anotherembodiment, it provides chemosensory receptor ligand modifiers capableof interacting with a chemosensory receptor via an interacting spacewithin the Venus flytrap domain that is outlined, defined, or shaped,partially or entirely, by interacting residues of the chemosensoryreceptor. In still yet another embodiment, it provides chemosensoryreceptor ligand modifiers excluding, e.g., natural or synthesized sweetenhancers known prior to the present invention.

In the context of the present invention, “capable of interacting with”or “interacting with” means that a compound or molecule binds to orforms one or more molecular interactions, e.g., productive interactionswith another molecule, e.g., a chemosensory receptor. Exemplarymolecular interactions, e.g., productive interactions include van derWaals, burial of hydrophobic atoms or atomic groups, hydrogen bonds,ring stacking interactions, salt-bridging electrostatic interactions, ora combination thereof.

In one embodiment, the present invention provides chemosensory receptorligand modifiers capable of interacting with a chemosensory receptor viaa group of interacting residues or a space within the Venus flytrapdomain that is outlined, shaped, or defined, partially or entirely bythe group or any subgroup of interacting residues, optionally in thepresence of a chemosensory receptor ligand, e.g., 1) S40, S144, S165,Y103, D142, P277 of a human T1R2, 2) K65, R383, D307, E302, and D278 ofa human T1R2, 3) I167, P185, T184, T326, E302, V384, A305, I325, I306,R383, D307, E382, D278, I279, I67, V66, V309, D142, S165, S40, S303,T242, F103, Q328, and S168 of a human T1R2, 4) S40, S144, S165, Y103,D142, P277, K65, R383, D307, E302, and D278 of a human T1R2, 5) S40,S144, S165, Y103, D142, P277, I167, P185, T184, T326, E302, V384, A305,I325, I306, R383, D307, E382, D278, I279, I67, V66, V309, S303, T242,F103, Q328, and S168 of a human T1R2, 6) K65, R383, D307, E302, D278,I167, P185, T184, T326, E302, V384, A305, I325, I306, E382, I279, I67,V66, V309, D142, S165, S40, S303, T242, F103, Q328, and S168 of a humanT1R2, 7) S40, S144, S165, Y103, D142, P277, K65, R383, D307, E302, D278,I167, P185, T184, T326, E302, V384, A305, I325, I306, E382, I279, I67,V66, V309, S303, T242, F103, Q328, and S168 of a human T1R2, 8) N143,S144, and I167 of a human T1R2, or 9) N143, S40, S144, S165, Y103, D142,P277, K65, R383, D307, E302, D278, I167, P185, T184, T326, E302, V384,A305, I325, I306, E382, I279, I67, V66, V309, S303, T242, F103, Q328,and S168 of a human T1R2.

In another embodiment, the present invention provides chemosensoryreceptor ligand enhancers capable of interacting with a chemosensoryreceptor in the presence of a chemosensory receptor ligand via one ormore interacting residues of K65, D278, L279, D307, R383, V384 of ahuman T1R2.

In yet another embodiment, the present invention provides sucrose orsucralose enhancers capable of interacting with a chemosensory receptorin the presence of sucrose or sucralose via one or more interactingresidues of S40, S144, Y103, D142, P277 of a human T1R2.

In still another embodiment, the present invention provides chemosensoryreceptor ligand modifiers capable of interacting with a chemosensoryreceptor, optionally in the presence of a chemosensory receptor ligandvia at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 interacting residuesselected from the group of N143, S40, S144, S165, Y103, D142, P277, K65,R383, D307, E302, D278, I167, P185, T184, T326, E302, V384, A305, I325,I306, E382, I279, I67, V66, V309, S303, T242, F103, Q328, and S168 of ahuman T1R2.

In still another embodiment, the present invention provides chemosensoryreceptor ligand modifiers capable of interacting with a chemosensoryreceptor to stabilize a conformation, e.g., semi-closed or closedconformation formed by the interaction between a chemosensory receptorand a chemosensory receptor ligand.

In still yet another embodiment, the present invention provideschemosensory receptor ligand modifiers, e.g., saccharin, saccharinanalogues, acesulfame K, acesulfame K analogues, or any compound capableof interacting with a chemosensory receptor via an interacting site thatis similar to or overlaps with an interacting site used by saccharin oracesulfame K. In one example, the present invention provideschemosensory receptor ligand enhancers, e.g., saccharin, saccharinanalogues, acesulfame K, or acesulfame K analogues that interact with achemosensory receptor via an interacting site including one or moreinteracting residues of K65, R383, D307, E302 and D278 of a human T1R2.

According to yet another aspect of the present invention, it provideschemosensory receptor modifiers. In one embodiment, it provideschemosensory receptor modifiers identified by the screen methods of thepresent invention. In another embodiment, it provides chemosensoryreceptor modifiers capable of interacting with a chemosensory receptorvia an interacting site of the present invention. In yet anotherembodiment, it provides chemosensory receptor modifiers capable ofinteracting with a chemosensory receptor via one or more interactingresidues of the chemosensory receptor. In still another embodiment, itprovides chemosensory receptor modifiers capable of interacting with achemosensory receptor via an interacting space within the Venus flytrapdomain that is outlined, defined, or shaped, partially or entirely, byinteracting residues of the chemosensory receptor. In still yet anotherembodiment, it provides chemosensory receptor modifiers excluding, e.g.,natural or synthesized sweet flavor entities known prior to the presentinvention.

In one embodiment, the present invention provides chemosensory receptormodifiers capable of interacting with a chemosensory receptor via agroup of interacting residues or a space within the Venus flytrap domainthat is outlined, shaped, or defined, partially or entirely by the groupor any subgroup of interacting residues, e.g., 1) S40, S144, S165, Y103,D142, P277 of a human T1R2, 2) K65, R383, D307, E302, and D278 of ahuman T1R2, 3) I167, P185, T184, T326, E302, V384, A305, I325, I306,R383, D307, E382, D278, I279, I67, V66, V309, D142, S165, S40, S303,T242, F103, Q328, and S168 of a human T1R2, 4) S40, S144, S165, Y103,D142, P277, K65, R383, D307, E302, and D278 of a human T1R2, 5) S40,S144, S165, Y103, D142, P277, I167, P185, T184, T326, E302, V384, A305,I325, I306, R383, D307, E382, D278, I279, I67, V66, V309, S303, T242,F103, Q328, and S168 of a human T1R2, 6) K65, R383, D307, E302, D278,I167, P185, T184, T326, E302, V384, A305, I325, I306, E382, I279, I67,V66, V309, D142, S165, S40, S303, T242, F103, Q328, and S168 of a humanT1R2, 7) S40, S144, S165, Y103, D142, P277, K65, R383, D307, E302, D278,I167, P185, T184, T326, E302, V384, A305, I325, I306, E382, I279, I67,V66, V309, S303, T242, F103, Q328, and S168 of a human T1R2, 8) N143,S144, and I167 of a human T1R2, or 9) N143, S40, S144, S165, Y103, D142,P277, K65, R383, D307, E302, D278, I167, P185, T184, T326, E302, V384,A305, I325, I306, E382, I279, I67, V66, V309, S303, T242, F103, Q328,and S168 of a human T1R2.

In still another embodiment, the present invention provides chemosensoryreceptor modifiers capable of interacting with a chemosensory receptorvia at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 interacting residuesselected from the group of N143, S40, S144, S165, Y103, D142, P277, K65,R383, D307, E302, D278, I167, P185, T184, T326, E302, V384, A305, I325,I306, E382, I279, I67, V66, V309, S303, T242, F103, Q328, and S168 of ahuman T1R2.

According to still another aspect of the present invention, it providesmethods for modulating a chemosensory receptor and/or its ligand bymodulating one or more interacting sites of the chemosensory receptor.For example, one can modulate a chemosensory receptor by contacting, invivo or in vitro, a chemosensory receptor modifier or chemosensoryreceptor ligand modifier or both, (e.g., optionally excluding naturalsweet flavor entity or sweet enhancers known prior to the presentinvention) with cells containing the chemosensory receptor, wherein thechemosensory receptor modifier or chemosensory receptor ligand iscapable of interacting with or targeting one or more interacting sitesof the chemosensory receptor.

In one embodiment, the method of modulating a chemosensory receptorand/or its ligand is by modulating one or more interacting residues orinteracting spaces or a combination thereof. In another embodiment, themethod of modulating a chemosensory receptor and/or its ligand is byinteracting with one or more interacting residues in the presence of achemosensory receptor ligand. In yet another embodiment, the method ofmodulating a chemosensory receptor or its ligand includes modulating theimpact of a chemosensory receptor ligand on the chemosensory receptor byinteracting with the chemosensory receptor via one or more interactingresidues in the presence of the chemosensory receptor ligand.

In yet another embodiment, the method of modulating a chemosensoryreceptor and/or its ligand is by interacting with the chemosensoryreceptor via a group of interacting residues or a space outlined,shaped, or defined, partially or entirely, by the group or subgroup ofinteracting residues, optionally in the presence of a chemosensoryreceptor ligand, e.g., 1) S40, S144, S165, Y103, D142, P277 of a humanT1R2, 2) K65, R383, D307, E302, and D278 of a human T1R2, 3) I167, P185,T184, T326, E302, V384, A305, I325, I306, R383, D307, E382, D278, I279,I67, V66, V309, D142, S165, S40, S303, T242, F103, Q328, and S168 of ahuman T1R2, 4) S40, S144, S165, Y103, D142, P277, K65, R383, D307, E302,and D278 of a human T1R2, 5) S40, S144, S165, Y103, D142, P277, I167,P185, T184, T326, E302, V384, A305, I325, I306, R383, D307, E382, D278,I279, I67, V66, V309, S303, T242, F103, Q328, and S168 of a human T1R2,6) K65, R383, D307, E302, D278, I167, P185, T184, T326, E302, V384,A305, I325, I306, E382, I279, I67, V66, V309, D142, S165, S40, S303,T242, F103, Q328, and S168 of a human T1R2, 7) S40, S144, S165, Y103,D142, P277, K65, R383, D307, E302, D278, I167, P185, T184, T326, E302,V384, A305, I325, I306, E382, I279, I67, V66, V309, S303, T242, F103,Q328, and S168 of a human T1R2, 8) N143, S144, and I167 of a human T1R2,or 9) N143, S40, S144, S165, Y103, D142, P277, K65, R383, D307, E302,D278, I167, P185, T184, T326, E302, V384, A305, I325, I306, E382, I279,I67, V66, V309, S303, T242, F103, Q328, and S168 of a human T1R2.

In yet another embodiment, the method of modulating a chemosensoryreceptor and/or its ligand is by interacting with the chemosensoryreceptor via one or more interacting residues of N143, S144, and I167 ofa human T1R2.

In yet another embodiment, the method of modulating a chemosensoryreceptor and/or its ligand is by interacting with the chemosensoryreceptor, optionally in the presence of a chemosensory receptor ligandvia one or more interacting residues of K65, D278, L279, D307, R383,V384 of a human T1R2.

In still another embodiment, the method of modulating a chemosensoryreceptor and/or its ligand is by interacting with the chemosensoryreceptor, optionally in the presence of sucrose or sucralose via one ormore interacting residues of S40, S144, Y103, D142, P277 of a humanT1R2.

In still another embodiment, the method of enhancing a chemosensoryreceptor and/or its ligand is by interacting with the chemosensoryreceptor, optionally in the presence of a chemosensory receptor ligandvia one or more interacting residues of K65, D278, L279, D307, R383,V384, S40, S144, Y103, D142, P277 of a human T1R2.

In still another embodiment, the method of modulating a chemosensoryreceptor and/or its ligand is by interacting with the chemosensoryreceptor, optionally in the presence of a chemosensory receptor ligandvia at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 interacting residuesselected from the group of N143, S40, S144, S165, Y103, D142, P277, K65,R383, D307, E302, D278, I167, P185, T184, T326, E302, V384, A305, I325,I306, E382, I279, I67, V66, V309, S303, T242, F103, Q328, and S168 of ahuman T1R2.

In still another embodiment, the method of modulating a chemosensoryreceptor and/or its ligand is by interacting with the chemosensoryreceptor, optionally in the presence of a chemosensory receptor ligandvia at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 interacting residuesselected from the group of N143, S40, S144, S165, Y103, D142, P277, K65,R383, D307, E302, D278, I167, P185, T184, T326, E302, V384, A305, I325,I306, E382, I279, I67, V66, V309, S303, T242, F103, Q328, and S168 of ahuman T1R2.

According to the present invention, a method of modulating achemosensory receptor and/or its ligand includes modulating theactivity, structure, function, expression, and/or modification of achemosensory receptor as well as modulating, treating, or takingprophylactic measure of a condition, e.g., physiological or pathologicalcondition, associated with a chemosensory receptor.

In general, a physiological or pathological condition associated with achemosensory receptor includes a condition associated with a taste,e.g., sweet, umami, bitter, sour, salty, or a combination thereof or acondition associated with, e.g., gastrointestinal system, metabolicdisorders, functional gastrointestinal disorders, etc.

In one embodiment, the method of the present invention, e.g., modulatinga chemosensory receptor and/or its ligand includes modulating,increasing or decreasing a sweet or umami taste or a subject's reaction,physiological or otherwise, to a sweet or umami taste. In anotherembodiment, the method of the present invention, e.g., modulating achemosensory receptor and/or its ligand includes enhancing a sweet orumami taste or a subject's reaction, physiological or otherwise, to asweet or umami taste.

In yet another embodiment, the method of the present invention, e.g.,modulating a chemosensory receptor and/or its ligand includesmodulation, treatment, and/or prophylactic measure of a conditionassociated with gastrointestinal system including without any limitationconditions associated with esophageal motility (e.g., cricopharyngealachalasia, globus hystericus, achalasia, diffuse esophageal spasm andrelated motor disorders, scleroderma involving the esophagus, etc.),inflammatory disorders (e.g., gastroesophageal reflux and esophagitis,infectious esophagitis, etc.), peptic ulcer, duodenal ulcer, gastriculcer, gastrinoma, stress ulcers and erosions, drug-associated ulcersand erosions, gastritis, esophageal cancer, tumors of the stomach,disorders of absorption (e.g., absorption of specific nutrients such ascarbohydrate, protein, amino acid, fat, cholesterol and fat-solublevitamins, water and sodium, calcium, iron, water-soluble vitamins,etc.), disorders of malabsorption, defects in mucosal function (e.g.,inflammatory or infiltrative disorders, biochemical or geneticabnormalities, endocrine and metabolic disorders, protein-losingenteropathy, etc.), autoimmune diseases of the digestive tract (e.g.,celiac disease, Crohn's disease, ulcerative colitis, etc.), irritablebowel syndrome, inflammatory bowel disease, complications ofinflammatory bowel disease, extraintestinal manifestations ofinflammatory bowel disease, disorders of intestinal motility, vasculardisorders of the intestine, anorectial disorders (e.g., hemorrhoids,anal inflammation, etc.), colorectal cancer, tumors of the smallintestine, cancers of the anus, derangements of hepatic metabolism,hyperbilirubinemia, hepatitis, alcoholic liver disease and cirrhosis,biliary cirrhosis, neoplasms of the liver, infiltrative and metabolicdiseases affecting the liver (e.g., fatty liver, reye's syndrome,diabetic glycogenosis, glycogen storage disease, Wilson's disease,hemochromatosis), diseases of the gallbladder and bile ducts, disordersof the pancreas (e.g., pancreatitis, pancreatic exocrine insufficiency,pancreatic cancer, etc.), endocrine tumors of the gastrointestinal tractand pancreas, etc.

In still another embodiment, the method of the present invention, e.g.,modulating a chemosensory receptor and/or its ligand includesmodulation, treatment, and/or prophylactic measure of a conditionassociated with metabolic disorders, e.g., appetite, body weight, foodor liquid intake or a subject's reaction to food or liquid intake, orstate of satiety or a subject's perception of a state of satiety,nutrition intake and regulation, (e.g., protein-energy malnutrition,physiologic impairments associated with protein-energy malnutrition,etc.), obesity, secondary obesity (e.g., hypothyroidism, Cushing'sdisease, insulinoma, hypothalamic disorders, etc.), eating disorders(e.g., anorexia nervosa, bulimia, etc.), vitamin deficiency and excess,insulin metabolism, diabetes (type I and type II) and complicationsthereof (e.g., circulatory abnormalities, retinopathy, diabeticnephropathy, diabetic neuropathy, diabetic foot ulcers, etc.), glucosemetabolism, fat metabolism, hypoglycemia, hyperglycemia,hyperlipoproteinemias, etc.

In still yet another embodiment, the method of the present invention,e.g., modulating a chemosensory receptor and/or its ligand includesmodulation, treatment, and/or prophylactic measure of a conditionassociated with functional gastrointestinal disorders, e.g., in theabsence of any particular pathological condition such as peptic ulcerand cancer, a subject has abdominal dyspepsia, e.g., feeling ofabdominal distention, nausea, vomiting, abdominal pain, anorexia, refluxof gastric acid, or abnormal bowel movement (constipation, diarrhea andthe like), optionally based on the retention of contents ingastrointestinal tract, especially in stomach. In one example,functional gastrointestinal disorders include a condition without anyorganic disease of the gastrointestinal tract, but with one or morereproducible gastrointestinal symptoms that affect the quality of lifeof a subject, e.g., human.

Exemplary functional gastrointestinal disorders include, without anylimitation, functional dyspepsia, gastroesophageal reflux condition,diabetic gastroparesis, reflux esophagitis, postoperativegastrointestinal dysfunction and the like, nausea, vomiting, sicklyfeeling, heartburn, feeling of abdominal distention, heavy stomach,belching, chest writhing, chest pain, gastric discomfort, anorexia,dysphagia, reflux of gastric acid, abdominal pain, constipation,diarrhea, breathlessness, feeling of smothering, low incentive or energylevel, pharyngeal obstruction, feeling of foreign substance, easyfatigability, stiff neck, myotonia, mouth dryness (dry mouth, thirst,etc.) tachypnea, burning sensation in the gastricintestinal tract, coldsensation of extremities, difficulty in concentration, impatience, sleepdisorder, headache, general malaise, palpitation, night sweat, anxiety,dizziness, vertigo, hot flash, excess sweating, depression, etc.

In still yet another embodiment, the method of the present invention,e.g., modulating a chemosensory receptor and/or its ligand includesincreasing or promoting digestion, absorption, blood nutrient level,and/or motility of gastrointestinal tract in a subject, e.g., promotionof gastric emptying (e.g., clearance of stomach contents), reduction ofabdominal distention in the early postprandial period, improvement ofanorexia, etc. In general, such promotion can be achieved eitherdirectly or via increasing the secretion of a regulatory entity, e.g.,hormones, etc.

In still yet another embodiment, the method of the present invention,e.g., modulating a chemosensory receptor and/or its ligand includesincreasing one or more gastrointestinal functions of a subject, e.g., toimprove the quality of life or healthy state of a subject.

In still yet another embodiment, the method of the present invention,e.g., modulating a chemosensory receptor and/or its ligand includesmodulating the activity of T1R (e.g., T1R1, T1R2, or T1R3) expressingcells, e.g., liver cells (e.g., hepatocytes, endothelial cells, Kupffercells, Stellate cells, epithelial cells of bile duct, etc.), heart cells(e.g., endothelial, cardiac, and smooth muscle cells, etc.), pancreaticcells (e.g., alpha cell, beta cell, delta cell, neurosecretory PP cell,D1 cell, etc.), cells in the nipple (e.g., ductal epithelial cells,etc.), stomach cells (e.g., mucous cells, parietal cells, chief cells, Gcells, P/D1 cells), intestinal cells (e.g., enteroendocrine cells, brushcells, etc.), salivary gland cells (e.g., Seromucous cells, mucouscells, myoepithelial cells, intercalated duct cell, striated duct cell,etc.), L cells (e.g., expressing GLP-1, etc.), enterochromaffin cells(e.g., expressing serotonin), enterochromaffin-like cells, G cells(e.g., expressing gastrin), D cells (delta cells, e.g., expressingsomatostatin), I cells (e.g., expressing cholescystokinin (CCK), K cells(e.g., expressing gastric inhibitory polypeptide), P/D1 cells (e.g.,expressing ghrelin), chief cells (e.g., expressing pepsin), and S cells(e.g., expressing secretin). In one example, the method of the presentinvention includes increasing the expression level of T1R in T1Rexpressing cells. In another example, the method of the presentinvention includes increasing the secretion level of T1R expressingcells.

In still yet another embodiment, the method of the present invention,e.g., modulating a chemosensory receptor and/or its ligand includesmodulating the expression, secretion, and/or functional level of T1Rexpressing cells associated with hormone, peptide, enzyme producing. Inone example, the method of the present invention includes modulating thelevel of glucose, e.g., inhibitors of a chemosensory receptor such asT1R2 can be used to decrease glucose level (e.g., glucose absorption) ina subject. In another example, the method of the present inventionincludes modulating the level of incretins, e.g., agonist of achemosensory receptor such as T1R2 can be used to increaseglucagons-like peotide 1 (GLP-1) and thus increase the production ofinsulin. In yet another example, the method of the present inventionincludes modulating the expression, secretion, and/or activity level ofhormones or peptides produced by T1R expressing cells orgastrointestinal hormone producing cells, e.g., ligands for 5HTreceptors (e.g., serotonin), incretins (e.g., GLP-1 andglucose-dependent insulinotropic polypeptide (GIP)), gastrin, secretin,pepsin, cholecystokinin, amylase, ghrelin, leptin, somatostatin, etc. Instill another example, the method of the present invention includesmodulating the pathways associated with hormones, peptides, and/orenzymes secreted by T1R expressing cells.

Exemplary chemosensory receptor ligand modifiers provided by the presentinvention and/or suitable to be used for methods of the presentinvention include compounds of the following formulae.

In a first aspect, a compound of structural Formula (I) is provided:

-   -   or a salt, hydrate, solvate or N-oxide thereof wherein:    -   G forms a single bond with either D or E and a double bond with        the other of D or E;    -   R¹ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN,        —NO₂, —OR³, —S(O)_(a)R³, —NR³R⁴, —CONR³R⁴, —CO₂R³, —NR³CO₂R⁴,        —NR³CONR⁴R⁵, —NR³CSNR⁴R⁵ or —NR³C(═NH)NR⁴R⁵, —SO₂NR²R³,        —NR²SO₂R³, —NR²SO₂NR³R⁴, —B(OR²)(OR³), —P(O)(OR²)(OR³) or        —P(O)(R²)(OR³);    -   R² is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN,        —NO₂, —OR⁶, —S(O)_(b)R⁶, —NR⁶R⁷, —CONR⁶R⁷, —CO₂R⁶, —NR⁶CO₂R⁷,        —NR⁶CONR⁷R⁸, —NR⁶CSNR⁷R⁸ or —NR⁶C(═NH)NR⁷R⁸, —SO₂NR⁵R⁶,        —NR⁵SO₂R⁶, —NR⁵SO₂NR⁶R⁷, —B(OR⁵)(OR⁶), —P(O)(OR⁵)(OR⁶),        —P(O)(R⁵)(OR⁶) or alternatively, R¹ and R² together with the        atoms to which they are bonded form an aryl, substituted aryl,        heteroaryl, substituted heteroaryl, cycloalkyl, substituted        cycloalkyl, cycloheteroalkyl or substituted cycloheteroalkyl        ring where the ring is optionally fused to another aryl,        substituted aryl, heteroaryl, substituted heteroaryl,        cycloalkyl, substituted cycloalkyl, cycloheteroalkyl or        substituted cycloheteroalkyl ring;    -   with the proviso that R¹ and R² are not both hydrogen;    -   A is hydrogen, alkyl, substituted alkyl, aryl, substituted aryl,        arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, halo,        —CN, —NO₂, —OR⁹, —S(O)_(c)R⁹, —NR⁹COR¹⁰, —NHOR⁹, —NR⁹R¹⁰, —NOR⁹,        —CONR⁹R¹⁰, —CO₂R⁹R¹⁰, —NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹,        —NR⁹C(═NH)NR¹⁰R¹¹, —B(OR¹⁰)(OR¹¹), —P(O)(OR¹⁰)(OR¹¹) or        —P(O)(R¹⁰)(OR¹¹);    -   B is —N— or —C(R¹²)—;    -   R¹² is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl,        —NR¹³R¹⁴, —CN, —OR¹³, —S(O)_(d)R¹³, —CO₂R¹³ or —CONR¹³R¹⁴;    -   G is —C— or —S(O)₂—;    -   provided that when G is —S(O)₂, G forms a single bond with E;    -   D is hydrogen, alkyl, substituted alkyl, aryl, substituted aryl,        arylalkyl, substituted arylalkyl, acyl, substituted acyl, halo,        chloro, fluoro, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl, substituted        heteroarylalkyl, —OR⁵, —NOR¹⁵, —S(O)_(c)R¹⁵, —NR¹⁵R¹⁶, —NCN,        —CO₂R¹⁵, —CONR¹⁵R¹⁶ when the bond between D and G is a single        bond;    -   D is ═O, ═S, ═N—OR¹⁵, ═NHNHR¹⁵ when G form a double bond with D;    -   n is 0 when G is —S(O)₂— and n is 1 when G is —C—;    -   E is —NR¹⁷, —N— or —C(R¹⁸)—;    -   provided that E is —NR¹⁷— only when G forms a single bond with        E;    -   R¹⁷ is alkyl, substituted alkyl, aryl, substituted aryl,        arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl or        —CO₂R¹⁹;    -   R¹⁸ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl,        —NR²⁰R²¹, —CN, OR²⁰, —S(O)_(f)R²⁰, —CO₂R²⁰ or —CONR²⁰R²¹;    -   a, b, c, d, e and f are independently 0, 1 or 2; and    -   R³-R¹¹, R¹³-R¹⁶, R¹⁸, R²⁰ and R²¹ are independently hydrogen,        alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl,        substituted arylalkyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively, R³ and R⁴, R⁴ and        R⁵, R⁶ and R⁷, R⁷ and R⁸, R⁹ and R¹⁰, R¹⁰ and R¹¹, R¹³ and R¹⁴,        R¹⁵ and R¹⁶ and R²⁰ and R²¹ together with the atoms to which        they are bonded form a cycloheteroalkyl or substituted        cycloheteroalkyl ring.

In some embodiments, R¹ is hydrogen, alkyl, substituted alkyl, —CN,—NO₂, —OR², —S(O)_(a)R³, —NR³R⁴, —CONR³R⁴, —CO₂R³ and R² is hydrogen,alkyl, substituted alkyl, —CN, —NO₂, —OR⁶, —S(O)_(b)R⁶, —NR⁶R⁷, —CONR⁶R⁷or —CO₂R⁶. In other embodiments, R¹ is hydrogen, —CH₃, —OH, —NH₂, —OR³or —CO₂R³ and R² is —CH₃, —OH, —NH₂, —OR⁶ or —CO₂R⁶ and R³ and R⁶ areindependently hydrogen or —CH₃. In still other embodiments, R¹ and R²together with the atoms to which they are bonded form an aryl,substituted aryl, heteroaryl, substituted heteroaryl, cycloalkyl,substituted cycloalkyl, cycloheteroalkyl or substituted cycloheteroalkylring.

In some embodiments, a compound of structural Formula (II) is provided:

-   -   wherein:    -   Y forms a single bond with either W or Z and a double bond with        the other of W or Z;    -   W is —C(R²⁴)—, —S—, —N—, —N(R²⁵)— or —O—;    -   Y is —C(R²⁶)— or —N—;    -   Z is —C(R²⁷)—, —S—, —N—, —N(R²⁸)—, or —O—;    -   R²⁴ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl —CN,        —NO₂, —OR²⁹, —S(O)_(g)R²⁹, —OCOR²⁹, —NR²⁹R³⁰, —CONR²⁹R³⁰,        —CO₂R²⁹, —NR²⁹COR³⁰, —SO₂NR²⁹R³⁰, —NR²⁹SO₂R³⁰, —B(OR²⁹)(OR³⁰),        —P(O)(OR²⁹)(OR³⁰) or —P(O)(R²⁹)(OR³⁰);    -   R²⁶ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl —CN,        —NO₂, —OR³¹, —S(O)_(h)R³¹, —OCOR³¹, —NR³¹R³², —CONR³¹R³²,        —CO₂R³¹, —NR³¹COR³², —SO₂NR³¹R³², —NR³¹SO₂R³², —B(OR³¹)(OR³²),        —P(O)(OR³¹)(OR³²) or —P(O)(R³¹)(OR³²);    -   R²⁷ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl —CN,        —NO₂, —OR³³, —S(O)_(i)R³³, —OCOR³³, —NR³³R³⁴, —CONR³³R³⁴,        —CO₂R³³, —NR³³COR³⁴, —SO₂NR³³R³⁴, —NR³³SO₂R³⁴, —B(OR³³)(OR³⁴),        —P(O)(OR³³)(OR³⁴) or —P(O)(R³³)(OR³⁴) or alternatively R²⁴ and        R²⁶ or R²⁶ and R²⁷ together with the atoms to which they are        bonded form a cycloalkyl, substituted cycloalkyl,        cycloheteroalkyl or substituted cycloheteroalkyl ring;    -   g, h and i are independently 0, 1 or 2;    -   R²⁵ and R²⁸ are independently hydrogen, alkyl, substituted        alkyl, aryl, substituted aryl, arylalkyl, substituted arylalkyl,        acyl, substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl; and    -   R²⁹-R³⁴ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl or        alternatively R²⁹ and R³⁰, R³¹ and R³² and R³³ and R³⁴ together        with the atoms to which they are bonded form a cycloheteroalkyl        or substituted cycloheteroalkyl ring; with the provisos that        with the provisos that when W is —O— or —S— or —NR²⁵ then Z is        —C(R²⁷) or —N—; Z is —O— or —S— or —NR²⁵ then W is —C(R²⁷) or        —N—; and    -   when B is —N— then A is not halo.

In some embodiments, W is —S—, NR²⁵, —N— —O— or —C(R²⁴)—, Y is —CR²⁶—and Z is —S—, —NR²⁸—, —N—, —O— or —C(R²⁷)—. In other embodiments, A ishydrogen, alkyl, substituted alkyl, aryl, substituted aryl, —OR¹, —SR¹,—CN, —NR⁹R¹⁰, —CONR⁹R¹⁰, —CO₂R⁹, —NR⁹CO₂R¹⁰, —NR⁹CONR¹⁰R¹¹,—NR⁹CSNR¹⁰R¹¹ or —NR⁹C(═NH)NR¹⁰R¹¹, D is —OR¹⁵, —S(O)_(e)R¹⁵, Cl,—NR¹⁵NR¹⁶, —CO₂R¹⁵ or —CONR¹⁵R¹⁶ or D is ═O, ═S, ═N—OR¹⁵ or ═NHNHR¹⁵ Bis —N—, W is —S—, NR²⁵, —N—, —O— or —C(R²⁴)—, Y is —CR²⁶— and Z is —S—,—NR²⁸—, —N—, —O— or —C(R²⁷)—. In still other embodiments, A is hydrogen,alkyl, substituted alkyl, aryl, substituted aryl, —OR¹, —SR¹, —CN,—NR⁸R⁹, —CONR⁸R⁹, —CO₂R⁸, —NR⁸CO₂R⁹, —NR⁸CONR⁹R¹⁰, —NR⁸CSNR⁹R¹⁰ or—NR⁸C(═NH)NR⁹R¹⁰, D is —OR¹⁵, —Cl, —S(O)_(e)R¹⁵, —NR¹⁵NR¹⁶, —CO₂R¹⁵ or—CONR¹⁵R¹⁶, or D is ═O, ═S, ═N—OR¹⁵ or ═NHNHR¹⁵, B is —N—, W is—C(R²⁴)—, —NR²⁵ or —N—, Y is —N— and Z is —C(R²⁷)—, —NR²⁸— or —N—. Instill other embodiments, W is —C(R²⁴)—, —NR²⁵ or —N—, Y is —N— and Z is—C(R²⁷)—, —NR²⁸— or —N—.

In some embodiments, a compound of structural Formula (IIa) is provided:

-   -   wherein:    -   A is hydrogen, alkyl, substituted alkyl, aryl, substituted aryl,        arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, halo,        —CN, —NO₂, —OR⁹, —S(O)_(c)R⁹, —NR⁹COR¹⁰, —NHOR⁹, —NR⁹R¹⁰, —NOR⁹,        —CONR⁹R¹⁰, —CO₂R⁹, —NR⁹CO₂R¹⁰, —NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹,        —NR⁹C(═NH)NR¹⁰R¹¹, —B(OR¹⁰)(OR¹¹), —P(O)(OR¹⁰)(OR¹¹) or        —P(O)(R¹⁰)(OR¹¹);    -   R¹⁷ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl or        —CO₂R¹⁹;    -   B is —N— or —C(R¹²)—;    -   R¹² is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl,        —NR¹³R¹⁴, —CN, —OR¹³, —S(O)_(d)R¹³, —CO₂R¹³ or —CONR¹³R¹⁴;    -   Y forms a single bond with either W or Z and a double bond with        the other of W or Z;    -   W is —C(R²⁴)—, —S—, —N—, —N(R²⁵)— or —O—;    -   Y is —C(R²⁶)— or —N—;    -   Z is —C(R²⁷)—, —S—, —N—, —N(R²⁸)— or —O—;    -   R²⁴ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl —CN,        —NO₂, —OR²⁹, —S(O)_(g)R²⁹, —OCOR²⁹, —NR²⁹R³⁰, —CONR²⁹R³⁰,        —CO₂R²⁹, —NR²⁹COR³⁰, —SO₂NR²⁹R³⁰, —NR²⁹SO₂R³⁰, —B(OR²⁹)(OR³⁰),        —P(O)(OR²⁹)(OR³⁰) or —P(O)(R²⁹)(OR³⁰);    -   R²⁶ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl —CN,        —NO₂, —OR³¹, —S(O)_(h)R³¹, —OCOR³¹, —NR³¹R³², —CONR³¹R³²,        —CO₂R³¹, —NR³¹COR³², —SO₂NR³¹R³², —NR³¹SO₂R³², —B(OR³¹)(OR³²),        —P(O)(OR³¹)(OR³²) or —P(O)(R³¹)(OR³²);    -   R²⁷ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl —CN,        —NO₂, —OR³³, —S(O)_(i)R³³, —OCOR³³, —NR³³R³⁴, —CONR³³R³⁴,        —CO₂R³³, —NR³³COR³⁴, —SO₂NR³³R³⁴, —NR³³SO₂R³⁴, —B(OR³³)(OR³⁴),        —P(O)(OR³³)(OR³⁴) or —P(O)(R³³)(OR³⁴) or alternatively R²⁴ and        R²⁶ or R²⁶ and R²⁷ together with the atoms to which they are        bonded form a cycloalkyl, substituted cycloalkyl,        cycloheteroalkyl or substituted cycloheteroalkyl ring;    -   c, d, g, h and i are independently 0 or 1 or 2;    -   R²⁵ and R²⁸ are independently hydrogen, alkyl, substituted        alkyl, aryl, substituted aryl, arylalkyl, substituted arylalkyl,        acyl, substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl; and    -   R⁹-R¹¹, R¹³, R¹⁴, R¹⁹ and R²⁹-R³⁴ are independently hydrogen,        alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl,        substituted arylalkyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl alternatively R⁹ and R¹⁰, R¹⁰ and        R¹¹, R¹³ and R¹⁴, R²⁹ and R³⁰, R³¹ and R³² and R³³ and R³⁴        together with the atoms to which they are bonded form a        cycloheteroalkyl or substituted cycloheteroalkyl ring;    -   with the provisos that: when W is —O— or —S— or —NR²⁵ then Z is        —C(R²⁷) or —N—; when Z is —O— or —S— or —NR²⁸ then W is —C(R²⁴)        or —N—; and    -   when B is —N— then A is not halo.

In some embodiments, A is hydrogen, alkyl, substituted alkyl, aryl,substituted aryl, arylalkyl, substituted arylalkyl, acyl, substitutedacyl, heteroalkyl, substituted heteroalkyl, heteroaryl, substitutedheteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN, —NO₂,—S(O)_(c)R⁹, —NR⁹R¹⁰, —CONR⁹R¹⁰, —CO₂R⁹ or —NR⁹CO₂R¹⁰. In otherembodiments, A is hydrogen, alkyl, substituted alkyl, aryl, substitutedaryl, —CN, —NO₂, —S(O)_(c)R⁹, —NR⁹R¹⁰, —CONR⁹R¹⁰, —CO₂R⁹ or —NR⁹CO₂R¹⁰.In still other embodiments, A is —OR⁹, —NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹ or—NR⁹C(═NH)NR¹⁰R¹¹. In still other embodiments, A is —OH, —NH₂, —NHCH₃,—N(CH₃)₂, —NHC(O)CH₃, —NOCH₃, —NHOCH₃, —NHC(O)OCH₃, —NHC(O)NH₂,—NHC(S)NH₂, —NHC(NH)NH₂, —CN, —CH₂OH, —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂,—CO₂H, —CONH₂, —CONHCH₃ or —CH₂NHC(O)CH₃.

In some embodiments, R¹⁷ is hydrogen, alkyl, substituted alkyl,arylalkyl, or substituted arylalkyl. In other embodiments, R¹⁷ ishydrogen, methyl, ethyl, propyl, iso-propyl, n-butyl, iso-butyl,sec-butyl, t-butyl, phenyl or benzyl.

In some embodiments, A is hydrogen, alkyl, substituted alkyl, aryl,substituted aryl, —CN, —NO₂, —S(O)_(c)R⁹, —NR⁹COR¹⁰, —NR⁹R¹⁰, —CONR⁹R¹⁰,—CO₂R⁹ or —NR⁹CO₂R¹⁰ and R¹⁷ is hydrogen, alkyl, substituted alkyl,arylalkyl, or substituted arylalkyl. In other embodiments, A is —OR⁹,—NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹ or —NR⁹C(═NH)NR¹⁰R¹¹ and R¹⁷ is hydrogen,alkyl, substituted alkyl, arylalkyl, or substituted arylalkyl. In stillother embodiments, A is —OH, —NH₂, —NHCH₃, —N(CH₃)₂, —NHC(O)CH₃, —NOCH₃,—NHOCH₃, —NHC(O)OCH₃, —NHC(O)NH₂, —NHC(S)NH₂, —NHC(NH)NH₂, —CN, —CH₂OH,—CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H, —CONH₂, —CONHCH₃ or—CH₂NHC(O)CH₃ and R¹⁷ is hydrogen, methyl, ethyl, propyl, iso-propyl,n-butyl, iso-butyl, sec-butyl, t-butyl, phenyl or benzyl.

In some embodiments, a compound of structural Formula (IIb) is provided:

-   -   wherein:    -   W is —C(R²⁴)— or —N—;    -   Y is —C(R²⁶)— or —N—; and    -   Z is —S—, —N(R²⁸)— or —O—. In some embodiments, W is —C(R²⁴)—, Y        is —C(R²⁶)— and Z is —S—, —N(R²⁸)— or —O—.

In some embodiments, R²⁴ is hydrogen, alkyl, substituted alkyl, acyl,substituted acyl, heteroalkyl, substituted heteroalkyl, —CN, —NO₂,—OR²⁹, —S(O)_(g)R²⁹, —OCOR²⁹, —NR²⁹R³⁰, —CONR²⁹R³⁰ or —CO₂R²⁹ and R²⁶ ishydrogen, alkyl, substituted alkyl, acyl, substituted acyl, heteroalkyl,substituted heteroalkyl, —CN, —NO₂, —OR³¹, —S(O)_(h)R³¹, —OCOR³¹,—NR³¹R³², —CONR³¹R³² or —CO₂R³¹. In other embodiments, R²⁴ is hydrogen,—CF₃, alkyl or substituted alkyl and R²⁶ is hydrogen, —CF₃, alkyl orsubstituted alkyl.

In some embodiments, A is hydrogen, alkyl, substituted alkyl, aryl,substituted aryl, —CN, —NO₂, —S(O)_(c)R⁹, —NR⁹R¹⁰, —CONR⁹R¹⁰, —CO₂R⁹ or—NR⁹CO₂R¹⁰, R¹⁷ is hydrogen, alkyl, substituted alkyl, arylalkyl, orsubstituted arylalkyl, R²⁴ is hydrogen, alkyl, substituted alkyl, acyl,substituted acyl, heteroalkyl, substituted heteroalkyl, —CN, —NO₂,—OR²⁹, —S(O)_(g)R²⁹, —OCOR²⁹, —NR²⁹R³⁰, —CONR²⁹R³⁰ or —CO₂R²⁹ and R²⁶ ishydrogen, alkyl, substituted alkyl, acyl, substituted acyl, heteroalkyl,substituted heteroalkyl, —CN, —NO₂, —OR³¹, —S(O)_(h)R³¹, —OCOR³¹,—NR³¹R³², —CONR³¹R³² or —CO₂R³¹. In other embodiments, A is —OR⁹,—NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹ or —NR⁹C(═NH)NR¹⁰R¹¹ and R¹⁷ is hydrogen,alkyl, substituted alkyl, arylalkyl, or substituted arylalkyl, R²⁴ ishydrogen, alkyl, substituted alkyl, acyl, substituted acyl, heteroalkyl,substituted heteroalkyl, —CN, —NO₂, —OR²⁹, —S(O)_(g)R²⁹, —OCOR²⁹,—NR²⁹R³⁰, —CONR²⁹R³⁰ or —CO₂R²⁹ and R²⁶ is hydrogen, alkyl, substitutedalkyl, acyl, substituted acyl, heteroalkyl, substituted heteroalkyl,—CN, —NO₂, —OR³¹, —S(O)_(h)R³¹, —OCOR³¹, —NR³¹R³², —CONR³¹R³² or—CO₂R³¹. In still other embodiments, A is —OH, —NH₂, —NHCH₃, —N(CH₃)₂,—NHOCH₃, —NOCH₃, —NHC(O)CH₃, —NHC(O)OCH₃, —NHC(O)NH₂, —NHC(S)NH₂,—NHC(NH)NH₂, —CN, —CH₂OH, —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H,—CONH₂, —CONHCH₃ or —CH₂NHC(O)CH₃, R¹⁷ is hydrogen, methyl, ethyl,propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, t-butyl, phenyl orbenzyl, R²⁴ is hydrogen, —CF₃, methyl, ethyl, propyl, iso-propyl,n-butyl, iso-butyl, sec-butyl or t-butyl and R²⁶ is hydrogen, —CF₃,methyl, ethyl, propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl ort-butyl.

In some embodiments, A is —NH₂, R¹⁷ is hydrogen or methyl, R²⁴ ishydrogen, —CF₃, methyl or ethyl and R²⁶ is hydrogen, —CF₃, methyl orethyl. In other embodiments, A is —NH₂, R¹⁷ is hydrogen or methyl, R²⁴is hydrogen, —CF₃, methyl or ethyl and R²⁶ is hydrogen, —CF₃, methyl orethyl.

In many of the above embodiments, R²⁸ is hydrogen, alkyl or arylalkyl.In many of the above embodiments, R²⁸ is hydrogen, methyl or benzyl. Insome of the above embodiments, Z is S.

In some embodiments, a compound of structural Formula (IIc) is provided:

-   -   wherein W is —S—, —N(R²⁵)— or —O—, Y is —C(R²⁶)— or —N— and Z is        —C(R²⁷)— or —N—. In some embodiments, W is —S—, —N(R²⁵)— or —O—,        Y is —C(R²⁶)— and Z is —C(R²⁷)—.

In some embodiments, R²⁷ is hydrogen, alkyl, substituted alkyl, acyl,substituted acyl, heteroalkyl, substituted heteroalkyl, —CN, —NO₂,—OR³³, —S(O)_(i)R³³, —OCOR³³, —NR³³R³⁴, —CONR³³R³⁴ or —CO₂R³³ and R²⁶ ishydrogen, alkyl, substituted alkyl, acyl, substituted acyl, heteroalkyl,substituted heteroalkyl, —CN, —NO₂, —OR³¹, —S(O)_(h)R³¹, —OCOR³¹,—NR³¹R³², —CONR³¹R³² or —CO₂R³¹. In other embodiments, R²⁷ is hydrogen,—CF₃, alkyl or substituted alkyl and R²⁶ is hydrogen, —CF₃, alkyl orsubstituted alkyl.

In some embodiments, A is hydrogen, alkyl, substituted alkyl, aryl,substituted aryl, —CN, —NO₂, —S(O)_(c)R⁹, —NR⁹R¹⁰, —CONR⁹R¹⁰, —CO₂R⁹ or—NR⁹CO₂R¹⁰, R¹⁷ is hydrogen, alkyl, substituted alkyl, arylalkyl, orsubstituted arylalkyl, R²⁷ is hydrogen, alkyl, substituted alkyl, acyl,substituted acyl, heteroalkyl, substituted heteroalkyl, —CN, —NO₂,—OR³³, —S(O)_(i)R³³, —OCOR³³, —NR³³R³⁴, —CONR³³R³⁴ or —CO₂R³³ and R²⁶ ishydrogen, alkyl, substituted alkyl, acyl, substituted acyl, heteroalkyl,substituted heteroalkyl, —CN, —NO₂, —OR³¹, —S(O)_(h)R³¹, —OCOR³¹,—NR³¹R³², —CONR³¹R³² or —CO₂R³¹. In other embodiments, A —OR⁹,—NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹ or —NR⁹C(═NH)NR¹⁰R¹¹ and R¹⁷ is hydrogen,alkyl, substituted alkyl, arylalkyl, or substituted arylalkyl, R²⁷ ishydrogen, alkyl, substituted alkyl, acyl, substituted acyl, heteroalkyl,substituted heteroalkyl, —CN, —NO₂, —OR³³, —S(O)_(i)R³³, —OCOR³³,—NR³³R³⁴, —CONR³³R³⁴ or —CO₂R³³ and R²⁶ is hydrogen, alkyl, substitutedalkyl, acyl, substituted acyl, heteroalkyl, substituted heteroalkyl,—CN, —NO₂, —OR³¹, —S(O)_(h)R³¹, —OCOR³¹, —NR³¹R³², —CONR³¹R³² or—CO₂R³¹. In still other embodiments, A is —OH, —NH₂, —NHCH₃, —N(CH₃)₂,—NHOCH₃, —NOCH₃, —NHC(O)CH₃, —NHC(O)OCH₃, —NHC(O)NH₂, —NHC(S)NH₂,—NHC(NH)NH₂, —CN, —CH₂OH, —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H,—CONH₂, —CONHCH₃ or —CH₂NHC(O)CH₃, R¹⁷ is hydrogen, methyl, ethyl,propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, t-butyl, phenyl orbenzyl, R²⁷ is hydrogen, —CF₃, methyl, ethyl, propyl, iso-propyl,n-butyl, iso-butyl, sec-butyl or t-butyl and R²⁶ is hydrogen, —CF₃,methyl, ethyl, propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl ort-butyl.

In some embodiments, A is —NH₂, R¹⁷ is hydrogen or methyl, R²⁷ ishydrogen, —CF₃, methyl or ethyl and R²⁶ is hydrogen, —CF₃, methyl orethyl. In other embodiments, R¹⁷ is hydrogen or methyl, R²⁷ is hydrogen,—CF₃, methyl or ethyl and R²⁶ is hydrogen, —CF₃, methyl or ethyl.

In some embodiments, R²⁵ is hydrogen, alkyl or arylalkyl. In otherembodiments, R²⁵ is hydrogen, methyl or benzyl. In still otherembodiments, Z is S.

In some embodiments, a compound of structural Formula (III) is provided:

-   -   wherein:    -   H is —C(R³⁵)— or —N—;    -   I is —C(R³⁶) or —N—;    -   J is —C(R³⁷)— or —N—;    -   K is —C(R³⁸)— or —N—;    -   R³⁵ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        halo, chloro, fluoro, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl, —CN, —NO₂, —OR³⁹, —S(O)_(j)R³⁹,        —OCOR³⁹, —NR³⁹R⁴⁰, —CONR³⁹R⁴⁰, —CO₂R³⁹, —SO₂NR³⁹R⁴⁰,        —NR³⁹SO₂R⁴⁰, —B(OR³⁹)(OR⁴⁰), —P(O)(OR³⁹)(OR⁴⁰) or        —P(O)(R³⁹)(OR⁴⁰);    -   R³⁶ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        halo, chloro, fluoro, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl, —CN, —NO₂, —OR⁴¹, —S(O)_(k)R⁴¹,        —OCOR⁴¹, —NR⁴¹COR⁴², —NR⁴¹R⁴², —CONR⁴¹R⁴², —CO₂R⁴¹, —SO₂NR⁴¹R⁴²,        —NR⁴¹SO₂R⁴², —B(OR⁴¹)(OR⁴²), —P(O)(OR⁴¹)(OR⁴²) or        —P(O)(R⁴¹)(OR⁴²);    -   R³⁷ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        halo, chloro, fluoro, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl, —CN, —NO₂, —OR⁴³, —S(O)_(l)R⁴³,        —OCOR⁴³, —NR⁴³COR⁴⁴, —NR⁴³R⁴⁴, —CONR⁴³R⁴⁴, —CO₂R⁴³, —SO₂NR⁴³R⁴⁴,        —NR⁴³SO₂R⁴⁴, —B(OR⁴³)(OR⁴⁴), —P(O)(OR⁴³)(OR⁴⁴) or        —P(O)(R⁴³)(OR⁴⁴);    -   R³⁸ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        halo, chloro, fluoro, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl, —CN, —NO₂, —OR⁴⁵, —S(O)_(m)R⁴⁵,        —OCOR⁴⁵, —NR⁴⁵COR⁴⁶, —NR⁴⁵R⁴⁶, —CONR⁴⁵R⁴⁶, —CO₂R⁴⁵, —SO₂NR⁴⁵R⁴⁶,        —NR⁴⁵SO₂R⁴⁶, —B(OR⁴⁵)(OR⁴⁶), —P(O)(OR⁴⁵)(OR⁴⁶) or        —P(O)(R⁴⁵)(OR⁴⁶);    -   j, k, 1 and m are independently 0, 1 or 2; and    -   R³⁹-R⁴⁶ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl or        alternatively R³⁹ and R⁴⁰, R⁴¹ and R⁴², R⁴³ and R⁴⁴ and R⁴⁵ and        R⁴⁶ together with the atoms to which they are bonded form a        cycloheteroalkyl or substituted cycloheteroalkyl ring;    -   with the proviso that at most, three of H, I, J and K are —N—.

In some embodiments, H is —C(R³⁵)— or —N—; I is —C(R³⁶)—; J is —C(R³⁷)—;and K is —C(R³⁸)— or —N—. In other embodiments, A is hydrogen, alkyl,substituted alkyl, aryl, substituted aryl, —OR¹, —SR¹, —CN, —NR⁹R¹⁰,—CONR⁹R¹⁰, —CO₂R⁹, —NR⁹CO₂R¹⁰, —NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹ or—NR⁹C(═NH)NR¹⁰R¹¹, D is —OR¹⁵, —NOR¹⁵, —S(O)_(e)R¹⁵, —NR¹⁵NR¹⁶, —CO₂R¹⁵or —CONR¹⁵R¹⁶ or D is ═O, ═S, ═N—OR¹⁵, B is —N—, H is —C(R³⁵)— or —N—, Iis —C(R³⁶)—, J is —C(R³⁷)— and K is —C(R³⁸)— or —N—.

In some embodiments, a compound of structural Formula (IIIa) isprovided:

-   -   or a salt, hydrate or solvate thereof wherein:    -   A is hydrogen, alkyl, substituted alkyl, aryl, substituted aryl,        arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, halo,        —CN, —NO₂, —OR⁹, —S(O)_(c)R⁹, —NR⁹R¹⁰, —NOR⁹, —NHOR⁹, —CONR⁹R¹⁰,        —CO₂R⁹, —NR⁹CO₂R¹⁰, —NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹,        —NR⁹C(═NH)NR¹⁰R¹¹, —B(OR¹⁰)(OR¹¹), —P(O)(OR¹⁰)(OR¹¹) or        —P(O)(R¹⁰)(OR¹¹);    -   R¹⁷ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl or        —CO₂R¹⁹;    -   B is —N— or —C(R¹²)—;    -   R¹² is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl,        —NR¹³R¹⁴, —CN, —OR¹³, —S(O)_(d)R¹³, —CO₂R¹³ or —CONR¹³R¹⁴;    -   H is —C(R³⁵)— or —N—;    -   I is —C(R³⁶) or —N—;    -   J is —C(R³⁷)— or —N—;    -   K is —C(R³⁸)— or —N—;    -   R³⁵ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        halo, chloro, fluoro, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl, —CN, —NO₂, —OR³⁹, —S(O)_(j)R³⁹,        —OCOR³⁹, —NR³⁹COR⁴⁰, —CONR³⁹R⁴⁰, CO₂R³⁹, SO₂NR³⁹R⁴⁰,        —NR³⁹SO₂R⁴⁰, —B(OR³⁹)(OR⁴⁰), —P(O)(OR³⁹)(OR⁴⁰) or        —P(O)(R³⁹)(OR⁴⁰);    -   R³⁶ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        halo, chloro, fluoro, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl, —CN, —NO₂, —OR⁴¹, —S(O)_(k)R⁴¹,        —OCOR⁴¹, —NR⁴¹COR⁴², —NR⁴¹R⁴², —CONR⁴¹R⁴², —CO₂R⁴¹, —SO₂NR⁴¹R⁴²,        —NR⁴¹SO₂R⁴², —B(OR⁴¹)(OR⁴²), —P(O)(OR⁴¹)(OR⁴²) or        —P(O)(R⁴¹)(OR⁴²);    -   R³⁷ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        halo, chloro, fluoro, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl, —CN, —NO₂, —OR⁴³, —S(O)_(l)R⁴³,        —OCOR⁴³, —NR⁴³R⁴⁴, —CONR⁴³R⁴⁴, —CO₂R⁴³, —SO₂NR⁴³R⁴⁴,        —NR⁴³SO₂R⁴⁴, —B(OR⁴³)(OR⁴⁴), —P(O)(OR⁴³)(OR⁴⁴) or        —P(O)(R⁴³)(OR⁴⁴);    -   R³⁸ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        halo, chloro, fluoro, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl, —CN, —NO₂, —OR⁴⁵, —S(O)_(m)R⁴⁵,        —OCOR⁴⁵, —NR⁴⁵COR⁴⁶, —NR⁴⁵R⁴⁶, —CONR⁴⁵R⁴⁶, —CO₂R⁴⁵, —SO₂NR⁴⁵R⁴⁶,        —NR⁴⁵SO₂R⁴⁶, —B(OR⁴⁵)(OR⁴⁶), —P(O)(OR⁴⁵)(OR⁴⁶) or        —P(O)(R⁴⁵)(OR⁴⁶);    -   c, d, j, k, 1 and m are independently 0, 1 or 2; and    -   R⁹, R¹³, R¹⁴, R¹⁹ and R³⁹-R⁴⁶ are independently hydrogen, alkyl,        substituted alkyl, aryl, substituted aryl, arylalkyl,        substituted arylalkyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively R¹³ and R¹⁴, R³⁹        and R⁴⁰, R⁴¹ and R⁴², R⁴³ and R⁴⁴ and R⁴⁵ and R⁴⁶ together with        the atoms to which they are bonded form a cycloheteroalkyl or        substituted cycloheteroalkyl ring;    -   with the proviso that at most, three of H, I, J and K are —N—.        In some embodiments, none of H, I, J, K are —N—.

In other embodiments, A is hydrogen, alkyl, substituted alkyl, aryl,substituted aryl, arylalkyl, substituted arylalkyl, acyl, substitutedacyl, heteroalkyl, substituted heteroalkyl, heteroaryl, substitutedheteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN, —NO₂,—S(O)_(c)R⁹, —NR⁹COR¹⁰, —NR⁹R¹⁰, —CONR⁹R¹⁰, —CO₂R⁹ or —NR⁹CO₂R¹⁰. Inother embodiments, A is hydrogen, alkyl, substituted alkyl, aryl,substituted aryl, —CN, —NO₂, —S(O)_(c)R⁹, —NR⁹R¹⁰, —CONR⁹R¹⁰, —CO₂R⁹ or—NR⁹CO₂R¹⁰. In still other embodiments, A is —OR⁹, —NR⁹CONR¹⁰R¹¹,—NR⁹CSNR¹⁰R¹¹ or —NR⁹C(═NH)NR¹⁰R¹¹. In still other embodiments, A is—OH, —NH₂, —NHCH₃, —N(CH₃)₂, —NHOCH₃, —NOCH₃, —NHC(O)CH₃, —NHC(O)OCH₃,—NHC(O)NH₂, —NHC(S)NH₂, —NHC(NH)NH₂, —CN, —CH₂OH, —CH₂NH₂, —CH₂NHCH₃,—CH₂N(CH₃)₂, —CO₂H, —CONH₂, —CONHCH₃ or —CH₂NHC(O)CH₃.

In some embodiments, R¹⁷ is hydrogen, alkyl, substituted alkyl,arylalkyl, or substituted arylalkyl. In other embodiments, R¹⁷ ishydrogen, methyl, ethyl, propyl, iso-propyl, n-butyl, iso-butyl,sec-butyl, t-butyl, phenyl or benzyl.

In some embodiments, A is hydrogen, alkyl, substituted alkyl, aryl,substituted aryl, —CN, —NO₂, —S(O)_(c)R⁹, —NR⁹R¹⁰, —CONR⁹R¹⁰, —CO₂R⁹,—NR⁹COR¹⁰ or —NR⁹CO₂R¹⁰ and R¹⁷ is hydrogen, alkyl, substituted alkyl,arylalkyl, or substituted arylalkyl. In other embodiments, A is —OR⁹,—NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹ or —NR⁹C(═NH)NR¹⁰R¹¹ and R¹⁷ is hydrogen,alkyl, substituted alkyl, arylalkyl, or substituted arylalkyl. In stillother embodiments, A is —OH, —NH₂, —NHCH₃, —N(CH₃)₂, —NHOCH₃, —NOCH₃,—NHC(O)CH₃, —NHC(O)OCH₃, —NHC(O)NH₂, —NHC(S)NH₂, —NHC(NH)NH₂, —CN,—CH₂OH, —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H, —CONH₂, —CONHCH₃ or—CH₂NHC(O)CH₃ and R¹⁷ is hydrogen, methyl, ethyl, propyl, iso-propyl,n-butyl, iso-butyl, sec-butyl, t-butyl, phenyl or benzyl.

In some embodiments, R³⁵ is hydrogen, —OH, —NR³⁹R⁴⁰, —NR³⁹COR⁴⁰,—OCOR³⁹, —CF₃, —OCF₃, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅, —CH(CH₃)₂,chloro, fluoro, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR³⁹R⁴⁰, —CO₂R⁴⁰,—SO₂NR³⁹R⁴⁰, —NR³⁹SO₂R⁴⁰, —B(OR³⁹)(OR⁴⁰), —P(O)(OR³⁹)(OR⁴⁰) or—P(O)(R³⁹)(OR⁴⁰); R³⁶ is hydrogen, —OH, —NR⁴¹R⁴², —NR⁴¹COR⁴², —OCOR⁴¹,—CF₃, —OCF₃, —OH, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅, —CH(CH₃)₂, chloro,fluoro, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁴¹R⁴², —CO₂R⁴¹, —SO₂NR⁴¹R⁴²,—NR⁴¹SO₂R⁴², —B(OR⁴¹)(OR⁴²), —P(O)(OR⁴¹)(OR⁴²) or —P(O)(R⁴¹)(OR⁴²); R³⁷is hydrogen, —OH, —NR⁴³R⁴⁴, —NR⁴³COR⁴⁴, —OCOR⁴³, —CF₃, —OCF₃, OH, —OCH₃,—OC₂H₅, —OC₃H₇, chloro, fluoro, —CH₃, —C₂H₅, —CH(CH₃)₂, —CH₂OH,—CH₂OCH₃, —CN, —C(O)NR⁴³R⁴⁴, —CO₂R⁴³, —SO₂NR⁴³R⁴⁴, —NR⁴³SO₂R⁴⁴,—B(OR⁴³)(OR⁴⁴), —P(O)(OR⁴³)(OR⁴⁴) or —P(O)(R⁴³)(OR⁴⁴); and R³⁸ ishydrogen, —OH, —NR⁴⁵R⁴⁶, —NR⁴⁵COR⁴⁶, —OCOR⁴⁵, —CF₃, —OCF₃, —OH, —OCH₃,—OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅, —CH(CH₃)₂, chloro, fluoro, —CH₂OH,—CH₂OCH₃, —CN, —C(O)NR⁴⁵R⁴⁶, —CO₂R⁴⁵, —SO₂NR⁴⁵R⁴⁶, —NR⁴⁵SO₂R⁴⁶,—B(OR⁴⁵)(OR⁴⁶), —P(O)(OR⁴⁵)(OR⁴⁶) or —P(O)(R⁴⁵)(OR⁴⁶). In otherembodiments, R³⁵ is hydrogen, —OH, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅,—CH(CH₃)₂, chloro, fluoro, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR³⁹R⁴⁰ or—CO₂R⁴⁰; R³⁶ is hydrogen, —OH, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅,—CH(CH₃)₂, chloro, fluoro, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁴¹R⁴² or—CO₂R⁴¹; R³⁷ is hydrogen, —OH, —OCH₃, —OC₂H₅, —OC₃H₇, chloro, fluoro,—CH₃, —C₂H₅, —CH(CH₃)₂, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁴³R⁴⁴, or —CO₂R⁴³;and R³⁸ is hydrogen, —OH, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅, —CH(CH₃)₂,chloro, fluoro, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁴⁵R⁴⁶ or —CO₂R⁴⁵.

In some embodiments, A is —NH₂, R¹⁷ is hydrogen, methyl, ethyl or benzylR³⁵, R³⁶, R³⁷ and R³⁸ independently hydrogen, methyl, —OH or OCH₃. Inother embodiments, A is —NH₂, R¹⁷ is hydrogen, methyl, ethyl or benzyland R³⁵, R³⁶, R³⁷ and R³⁸ are independently hydrogen, methyl, —OH orOCH₃. In still other embodiments, A is —NH₂, R¹⁷ is hydrogen or methyl,and R³⁵, R³⁶, R³⁷ and R³⁸ are independently hydrogen or methyl. In stillother embodiments, A is —NH₂, R¹⁷ is hydrogen or methyl, and R³⁵, R³⁶,R³⁷ and R³⁸ are independently hydrogen or methyl. In still otherembodiments, B is —N—.

In some embodiments, a compound of structural Formula (IV) is provided:

-   -   wherein:    -   L is —CHR⁶⁰—, —NR⁴⁷, —O— or —S—;    -   M is —CHR⁶¹—, —NR⁴⁸, —O— or —S—;    -   R is —CHR⁶²—, —NR⁴⁹, —O— or —S—;    -   T is —CHR⁶³—, —NR⁵⁰, —O— or —S—;    -   o and p are independently 0 or 1;    -   R⁶⁰ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl, —CN,        —NO₂, —OR⁶⁴, —S(O)_(t)R⁶⁴, —OCOR⁶⁴, —NR⁶⁴COR⁶⁵, —NR⁶⁴R⁶⁵,        —CONR⁶⁴R⁶⁵, —CO₂R⁶⁴, —SO₂NR⁶⁴R⁶⁵, —NR⁶⁴SO₂R⁶⁵, —B(OR⁶⁴)(OR⁶⁵),        —P(O)(OR⁶⁴)(OR⁶⁵) or —P(O)(R⁶⁴)(OR⁶⁵);    -   R⁶¹ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl, —CN,        —NO₂, —OR⁶⁶, —S(O)_(u)R⁶⁶, —OCOR⁶⁶, —NR⁶⁶COR⁶⁷, —NR⁶⁶R⁶⁷,        —CONR⁶⁶R⁶⁷, —CO₂R⁶⁶, —SO₂NR⁶⁶R⁶⁷, —NR⁶⁶SO₂R⁶⁷, —B(OR⁶⁶)(OR⁶⁷),        —P(O)(OR⁶⁶)(OR⁶⁷) or —P(O)(R⁶⁶)(OR⁶⁷);    -   R⁶² is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl, —CN,        —NO₂, —OR⁶⁸, —S(O)_(v)R⁶⁸, —OCOR⁶⁸, —NR⁶⁸COR⁶⁹, —NR⁶⁸R⁶⁹,        —CONR⁶⁸R⁶⁹, —CO₂R⁶⁸, —SO₂NR⁶⁸R⁶⁹, —NR⁶⁸SO₂R⁶⁹, —B(OR⁶⁸)(OR⁶⁹),        —P(O)(OR⁶⁸)(OR⁶⁹) or —P(O)(R⁶⁸)(OR⁶⁹);    -   R⁶³ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl, —CN,        —NO₂, —OR⁷⁰, —S(O)_(x)R⁷⁰, —OCOR⁷⁰, —NR⁷⁰COR⁷¹, —NR⁷⁰R⁷¹,        —CONR⁷⁰R⁷¹, —CO₂R⁷⁰, —SO₂NR⁷⁰R⁷¹, —NR⁷⁰SO₂R⁷¹, —B(OR⁷⁰)(OR⁷¹),        —P(O)(OR⁷⁰)(OR⁷¹) or —P(O)(R⁷⁰)(OR⁷¹);    -   t, u, v and x are independently 0, 1 or 2;    -   R⁶⁴-R⁷¹ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl or        alternatively R⁶⁴ and R⁶⁵, R⁶⁶ and R⁶⁷, R⁶⁸ and R⁶⁹ and R⁷⁰ and        R⁷¹ together with the atoms to which they are bonded form a        cycloheteroalkyl or substituted cycloheteroalkyl ring; and    -   R⁴⁷-R⁵⁰ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl;    -   with the provisos that that at most only one of L, M, R and T is        a heteroatom.

In some embodiments, L, R and T are —CH₂, o and p are 1 and M is—N(R⁴⁸)—, —S— or —O— and R⁴⁸ is hydrogen, —CH₃ or —COCH₃. In otherembodiments, A is hydrogen, alkyl, substituted alkyl, aryl, substitutedaryl, —OR⁹, —SR⁹, —CN, —NR⁹R¹⁰, —CONR⁹R¹⁰, —CO₂R⁹, —NR⁹CO₂R¹⁰,—NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹ or —NR⁹C(═NH)NR¹⁰R¹¹, D is —OR¹⁵, —NOR¹⁵,—S(O)_(e)R¹⁵, —NR¹⁵NR¹⁶, —CO₂R¹⁵ or —CONR¹⁵R¹⁶ or D is ═O, ═S, ═N—OR¹⁵,B is —N—, L, R and T are —CH₂, o and p are 1 and M is —N(R⁴⁸)—, —S— or—O— and R⁴⁸ is hydrogen, —CH₃ or —COCH₃.

In some of the above embodiments, A is hydrogen, alkyl, substitutedalkyl, aryl, substituted aryl, —OR⁹, —SR⁹, —CN, —NR⁹R¹⁰, —CONR⁹R¹⁰,—CO₂R⁹, —NR⁹CO₂R¹⁰, —NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹ or —NR⁹C(═NH)NR¹⁰R¹¹.In other of the above embodiments, A is —OH, —NH₂, —NHCH₃, —N(CH₃)₂,—NHC(O)CH₃, —NHC(O)OCH₃, —NHOCH₃, —NOCH₃, —NHC(O)NH₂, —NHC(S)NH₂,—NHC(NH)NH₂, —CN, —CH₂OH, —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H,—CONH₂, —CONHCH₃ or —CH₂NHC(O)CH₃.

In some of the above embodiments, D is —OR¹⁵, —S(O)_(e)R¹⁵, —NR¹⁵NR¹⁶,—CO₂R¹⁵, —CONR¹⁵R¹⁶, Cl, ═N—OR¹⁵ or ═NHNHR¹⁵. In other of the aboveembodiments, D is —OH, —SH or —NH₂.

In some of the above embodiments, R¹⁷ is hydrogen, alkyl, substitutedalkyl, arylalkyl, or substituted arylalkyl. In some of the aboveembodiments, R¹⁷ is hydrogen, —CH₃, —CH₂CH₃ or —CH₂Ph.

In some of the above embodiments, R¹² is hydrogen, alkyl, substitutedalkyl, aryl, substituted aryl, —OR¹³, —SR¹³, —CN, —CONR¹³R¹⁴ or —CO₂R¹².In other of the above embodiments, R¹² is hydrogen, —OH, —SH, —CN,—CH₂OH or —CO₂H.

In some of the above embodiments, A is hydrogen, alkyl, substitutedalkyl, aryl, substituted aryl, —OR¹, —SR¹, —CN, —NR⁹R¹⁰, —CONR⁹R¹⁰,—CO₂R⁹, —NR⁹CO₂R¹⁰, —NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹ or —NR⁹C(═NH)NR¹⁰R¹¹, Dis —OR¹⁵, Cl, —S(O)_(e)R¹⁵, —NR¹⁵NR¹⁶, —CO₂R¹⁵ or —CONR¹⁵R¹⁶ or D is ═O,═S, ═N—OR¹⁵, ═NHNHR¹⁵ and R¹² is hydrogen, alkyl, substituted alkyl,aryl, substituted aryl, —OR¹³, —SR¹³, —CN, —CONR¹³R¹⁴ or —CO₂R¹³. Inother of the above embodiments, A is —OH, —NH₂, —NHCH₃, —N(CH₃)₂,—NHOCH₃, —NOCH₃, —NHC(O)CH₃, —NHC(O)OCH₃, —NHC(O)NH₂, —NHC(S)NH₂,—NHC(NH)NH₂, —CN, —CH₂OH, —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H,—CONH₂, —CONHCH₃, or —CH₂NHC(O)CH₃, D is OH, SH or NH₂ or D is ═O, ═S,═N—OR¹⁵ or ═NHNHR¹⁵ and R¹² is hydrogen, —OH, —SH, —CN, —CH₂OH or —CO₂H.

In some of the above embodiments, A is hydrogen, alkyl, substitutedalkyl, aryl, substituted aryl, —OR¹, —SR¹, —CN, —NR⁹R¹⁰, —CONR⁹R¹⁰,—CO₂R⁹, —NR⁹CO₂R¹⁰, —NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹ or —NR⁹C(═NH)NR¹⁰R¹¹and R¹⁷ is hydrogen, alkyl, substituted alkyl, arylalkyl or substitutedarylalkyl. In other of the above embodiments, A is —OH, —NH₂, —NHCH₃,—N(CH₃)₂, —NHOCH₃, —NOCH₃, —NHC(O)CH₃, —NHC(O)OCH₃, —NHC(O)NH₂,—NHC(S)NH₂, —NHC(NH)NH₂, —CN, —CH₂OH, —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂,—CO₂H, —CONH₂, —CONHCH₃, or —CH₂NHC(O)CH₃ and R¹⁷ is hydrogen, —CH₃,—CH₂CH₃ or —CH₂Ph.

In some of the above embodiments, A is hydrogen, alkyl, substitutedalkyl, aryl, substituted aryl, —OR¹, —SR¹, —CN, —NR⁸R⁹, —CONR⁸R⁹,—CO₂R⁸, —NR⁸CO₂R⁹, —NR⁸CONR⁹R¹⁰, —NR⁸CSNR⁹R¹⁰ or —NR⁸C(═NH)NR⁹R¹⁰, G is—S(O)₂— and R¹² is hydrogen, alkyl, substituted alkyl, aryl, substitutedaryl, —OR¹³, —SR¹³, —CN, —CONR¹³R¹⁴ or —CO₂R¹⁴. In other of the aboveembodiments, A is —OH, —NH₂, —NHCH₃, —N(CH₃)₂, —NHOCH₃, —NOCH₃,—NHC(O)CH₃, —NHC(O)OCH₃, —NHC(O)NH₂, —NHC(S)NH₂, —NHC(NH)NH₂, —CN,—CH₂OH, —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H, —CONH₂, —CONHCH₃, or—CH₂NHC(O)CH₃, G is —S(O)₂— and R¹² is hydrogen, —OH, —SH, —CN, —CH₂OHor —CO₂H.

In some of the above embodiments, A is hydrogen, alkyl, substitutedalkyl, aryl, substituted aryl, —OR¹, —SR¹, —CN, —NR⁸R⁹, —CONR⁸R⁹,—CO₂R⁸, —NR⁸CO₂R⁹, —NR⁸CONR⁹R¹⁰, —NR⁸CSNR⁹R¹⁰ or —NR⁸C(═NH)NR⁹R¹⁰, G is—S(O)₂— and R¹⁷ is hydrogen, alkyl, substituted alkyl, arylalkyl orsubstituted arylalkyl. In other of the above embodiments, A is —NH₂,—NHCH₃, —N(CH₃)₂, —NHOCH₃, —NOCH₃, —NHC(O)CH₃, —NHC(O)OCH₃, —NHC(O)NH₂,—NHC(S)NH₂, —NHC(NH)NH₂, —CN, —CH₂OH, —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂,—CO₂H, —CONH₂, —CONHCH₃, or —CH₂NHC(O)CH₃, G is —S(O)₂— and R¹⁷ ishydrogen, —CH₃, —CH₂CH₃ or —CH₂Ph.

In some embodiments, a compound of structural Formula (V) is provided:

-   -   wherein:    -   D is hydrogen, alkyl, aryl, halo, chloro, fluoro, —OH, —NH₂,        —SR⁵¹, —CH₃, phenyl, —CO₂H or —CONH₂;    -   R⁵¹ is hydrogen, alkyl, substituted alkyl, aryl alkyl, —CH₃,        —CH₂CH₃, benzyl or —CH₂CO₂C₂H₅;    -   A is —NH₂, —NHCH₃, —N(CH₃)₂, —NHC(O)CH₃, —NHC(O)OCH₃,        —NHC(O)NH₂, —NHOCH₃, —NOCH₃, —NHC(S)NH₂, —NHC(NH)NH₂, —CN,        —CH₂OH, —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H, —CONH₂,        —CONHCH₃, or —CH₂NHC(O)CH₃;    -   R⁵² is hydrogen, methyl, ethyl, alkyl, chloro, fluoro, —CO₂R⁵⁴,        —CONR⁵⁴R⁵⁵, —SO₂NR⁵⁴R⁵⁵, —NR⁵⁴SO₂R⁵⁵, —B(OR⁵⁴)(OR⁵⁵),        —P(O)(OR⁵⁴)(OR⁵⁵) or —P(O)(R⁵⁴)(OR⁵⁵);    -   R⁵³ is hydrogen, alkoxy, alkyl, substituted alkyl, chloro,        fluoro, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅, —CH(CH₃)₂, —CH₂OH,        —CH₂OCH₃, —CN, —C(O)NR⁵⁶R⁵⁷, —CO₂R⁵⁶, —SO₂NR⁵⁶R⁵⁷, —NR⁵⁶SO₂R⁵⁷,        —B(OR⁵⁶)(OR⁵⁷), —P(O)(OR⁵⁶)(OR⁵⁷) or —P(O)(R⁵⁶)(OR⁵⁷); and    -   R⁵⁴-R⁵⁷ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl or        alternatively R⁵⁴ and R⁵⁵ and R⁵⁶ and R⁵⁷ together with the        atoms to which they are bonded form a cycloheteroalkyl or        substituted cycloheteroalkyl ring;    -   provided that when R⁵² and R⁵³ are hydrogen then D is —SH and A        is —NH₂.

In some embodiments, R⁵¹ is alkyl, substituted alkyl, aryl alkyl, —CH₃,—CH₂CH₃, benzyl or —CH₂CO₂C₂H₅, R⁵² is hydrogen, methyl, ethyl, alkyl,—CO₂R⁵⁴, —CONR⁵⁴R⁵⁵, —SO₂NR⁵⁴R⁵⁵, —NR⁵⁴SO₂R⁵⁵, —B(OR⁵⁴)(OR⁵⁵),—P(O)(OR⁵⁴)(OR⁵⁵) or —P(O)(R⁵⁴)(OR⁵⁵) and R⁵³ is hydrogen, alkoxy,alkyl, substituted alkyl, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅, —CH(CH₃)₂,—CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁵⁶R⁵⁷, —CO₂R⁵⁶, —SO₂NR⁵⁶R⁵⁷, —NR⁵⁶SO₂R⁵⁷,—B(OR⁵⁶)(OR⁵⁷), —P(O)(OR⁵⁶)(OR⁵⁷) or —P(O)(R⁵⁶)(OR⁵⁷).

In some embodiments, when D is methyl, A is dimethylamino and R⁵³ ishydrogen then R⁵² is not methyl, ethyl or carboxyl; when D is methyl, Ais dimethylamino and R⁵³ is methyl then R⁵² is not methyl; when D is—SCH₃, A is dimethylamino and R⁵³ is hydrogen then R⁵² is notcarboethoxy; when D is hydrogen, A is dimethylamino and R⁵³ is hydrogenthen R⁵² is not carboxyl or carboethoxy; when D is hydrogen, A isdimethylamino and R⁵³ is methyl then R⁵² is not methyl; when D ishydrogen, A is methylamino and R⁵³ is hydrogen then R⁵² is not methyl,ethyl or carboethoxy; when D is hydrogen, A is methylamino and R⁵³ ismethyl then R⁵² is not methyl or carboethoxy; when D is hydrogen, A ismethylamino and R⁵³ is —CH₂NMe then R⁵² is not methyl or carboethoxy;when D is phenyl, A is methylamino and R⁵³ is hydrogen then R⁵² is notmethyl; when D is phenyl, A is —NH(CO)CH₃ and R⁵³ is methyl then R⁵² isnot carbomethoxy.

In some embodiments, a compound of structural formula (VI) is provided:

-   -   where R⁵⁸ is hydrogen, —CH₃, —C₂H₅, phenyl or benzyl.

In other embodiments, a compound of structural formula (VII) isprovided:

-   -   where A is hydrogen, —CH₃, —C₂H₅, phenyl or benzyl.

In still other embodiments, a compound of structural formula (VIII) isprovided:

-   -   where R⁸, R⁹ are independently hydrogen, —CH₃, —C₂H₅, phenyl or        benzyl provided that both R⁸ and R⁹ are not hydrogen.

In still other embodiments, a compound of structural formula (IX) isprovided:

-   -   wherein R⁵² is —OCH₃, —OC₂H₅, —OC₃H₇, —C₂H₅, —CH(CH₃)₂, —CH₂OH,        —CH₂OCH₃, —CN, —C(O)NR⁵⁴R⁵⁵, —CO₂R⁵⁴, —SO₂NR⁵⁴R⁵⁵, —NR⁵⁴SO₂R⁵⁵,        —B(OR⁵⁴)(OR⁵⁵), —P(O)(OR⁵⁴)(OR⁵⁵), —P(O)(R⁵⁴)(OR⁵⁵) or        substituted alkyl;    -   R⁵³ is methyl, alkyl, CO₂R⁵⁶ or —CONR⁵⁶R⁵⁷, —SO₂NR⁵⁶R⁵⁷,        —NR⁵⁶SO₂R⁵⁷, —B(OR⁵⁶)(OR⁵⁷), —P(O)(OR⁵⁶)(OR⁵⁷) or        —P(O)(R⁵⁶)(OR⁵⁷); and    -   R⁵⁴-R⁵⁷ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively, R⁵⁴ and R⁵⁵ and        R⁵⁶ and R⁵⁷ together with the atoms to which they are bonded        form a cycloheteroalkyl or substituted cycloheteroalkyl ring.

In still other embodiments, a compound of structural formula (X) isprovided:

-   -   where D is —OH, —SH or —NH₂, R⁵² is —OCH₃, —OC₂H₅, —OC₃H₇,        —C₂H₅, —CH(CH₃)₂, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁵⁴R⁵⁵, —CO₂R⁵⁴        or substituted alkyl, R⁵² is —OCH₃, —OC₂H₅, —OC₃H₇, —C₂H₅,        —CH(CH₃)₂, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁵⁴R⁵⁵, —CO₂R⁵⁴,        —SO₂NR⁵⁴R⁵⁵, —NR⁵⁴SO₂R⁵⁵, —B(OR⁵⁴)(OR⁵⁵), —P(O)(OR⁵⁴)(OR⁵⁵),        —P(O)(R⁵⁴)(OR⁵⁵) or substituted alkyl and R⁵⁴ and R⁵⁵ are        independently hydrogen, alkyl, substituted alkyl, aryl,        substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively R⁵⁴ and R⁵⁵        together with the atoms to which they are bonded form a        cycloheteroalkyl or substituted cycloheteroalkyl ring.

In some embodiments, compounds having the structure below are provided:

-   -   where R⁵¹ is —CH₃, —CH₂CH₃, benzyl or —CH₂CO₂CH₂CH₃.

In other embodiments, a compound having the structure below is provided:

In still other embodiments, a compound having the structure below isprovided:

In still other embodiments, compounds having the structure below areprovided:

In still other embodiments, compounds having the structures below areprovided:

In still other embodiments, compounds having the structures below areprovided:

-   -   wherein R¹² is —OH, —SH, —CN, —CH₂OH, —CO₂R¹³ or —CONR¹³R¹⁴.

In some embodiments, compounds having the structure below are provided:

In some embodiments, a compound having the structure below is provided:

In some embodiments, a compound having the structure below is provided:

In still other embodiments, compounds having the structures below areprovided:

In still other embodiments, compounds having the structure below areprovided:

In still other embodiments, compounds having the structure below areprovided:

In some embodiments, a compound of structural Formula (XI) is provided:

-   -   wherein:    -   R¹² is —OH, —SH, —CN, —CH₂OH, —CO₂R¹³ or —CONR¹³R¹⁴;    -   D is —OH or —SH;    -   A is —OH, —NH₂, —NHCH₃, —N(CH₃)₂, —NHOCH₃, —NOCH₃, —NHC(O)CH₃,        —NHC(O)OCH₃, —NHC(O)NH₂, —NHC(S)NH₂, —NHC(NH)NH₂, —CN, —CH₂OH,        —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H, —CONH₂, —CONHCH₃ or        —CH₂NHC(O)CH₃;    -   R³⁵ is hydrogen, —OH, —OCH₃, —OC₂H₅, —OC₃H₇, alkyl, —CH₃, —C₂H₅,        —CH(CH₃)₂, chloro, fluoro, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR³⁹R⁴⁰,        —CO₂R⁴⁰, —SO₂NR³⁹R⁴⁰, —NR³⁹SO₂R⁴⁰, —B(OR³⁹)(OR⁴⁰),        —P(O)(OR³⁹)(OR⁴⁰) or —P(O)(R³⁹)(OR⁴⁰);    -   R³⁶ is hydrogen, —OH, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅,        —CH(CH₃)₂, chloro, fluoro, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁴¹R⁴²,        —CO₂R⁴¹, —SO₂NR⁴¹R⁴², —NR⁴¹SO₂R⁴², —B(OR⁴¹)(OR⁴²),        —P(O)(OR⁴¹)(OR⁴²) or —P(O)(R⁴¹)(OR⁴²);    -   R³⁷ is hydrogen, —OH, —OCH₃, —OC₂H₅, —OC₃H₇, chloro, fluoro,        —CH₃, —C₂H₅, —CH(CH₃)₂, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁴³R⁴⁴,        —CO₂R⁴³, —SO₂NR⁴³R⁴⁴, —NR⁴³SO₂R⁴⁴, —B(OR⁴³)(OR⁴⁴),        —P(O)(OR⁴³)(OR⁴⁴) or —P(O)(R⁴³)(OR⁴⁴);    -   R³⁸ is hydrogen, —OH, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅,        —CH(CH₃)₂, chloro, fluoro, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁴⁵R⁴⁶,        —CO₂R⁴⁵, —SO₂NR⁴⁵R⁴⁶, —NR⁴⁵SO₂R⁴⁶, —B(OR⁴⁵)(OR⁴⁶),        —P(O)(OR⁴⁵)(OR⁴⁶) or —P(O)(R⁴⁵)(OR⁴⁶); and    -   R³⁹-R⁴⁶ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl or        alternatively R³⁹ and R⁴⁰, R⁴¹ and R⁴², R⁴³ and R⁴⁴ and R⁴⁵ and        R⁴⁶ together with the atoms to which they are bonded form a        cycloheteroalkyl or substituted cycloheteroalkyl ring;    -   provided that when R¹² is hydrogen then R³⁶, R³⁷, R³⁸ and R³⁹        are not hydrogen. In some embodiments, R¹² is —OH, —SH, —CN,        —CH₂OH or —CO₂H.

In some embodiments, R³⁵ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃,—C₂H₅, —CH(CH₃)₂, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR³⁹R⁴⁰, —CO₂R⁴⁰,—SO₂NR³⁹R⁴⁰, —NR³⁹SO₂R⁴⁰, —B(OR³⁹)(OR⁴⁰), —P(O)(OR³⁹)(OR⁴⁰) or—P(O)(R³⁹)(OR⁴⁰), R³⁶ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅,—CH(CH₃)₂, —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁴¹R⁴², —CO₂R⁴¹, —SO₂NR⁴¹R⁴²,—NR⁴¹SO₂R⁴², —B(OR⁴¹)(OR⁴²), —P(O)(OR⁴¹)(OR⁴²) or —P(O)(R⁴¹)(OR⁴²), R³⁷is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅, —CH(CH₃)₂, —CH₂OH,—CH₂OCH₃, —CN, —C(O)NR⁴³R⁴⁴, —CO₂R⁴³, —SO₂NR⁴³R⁴⁴, —NR⁴³SO₂R⁴⁴,—B(OR⁴³)(OR⁴⁴), —P(O)(OR⁴³)(OR⁴⁴) or —P(O)(R⁴³)(OR⁴⁴) and R³⁸ ishydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, alkyl, —CH₃, —C₂H₅, —CH(CH₃)₂, —CH₂OH,—CH₂OCH₃, —CN, —C(O)NR⁴⁵R⁴⁶, —CO₂R⁴⁵, —SO₂NR⁴⁵R⁴⁶, —NR⁴⁵SO₂R⁴⁶,—B(OR⁴⁵)(OR⁴⁶), —P(O)(OR⁴⁵)(OR⁴⁶) or —P(O)(R⁴⁵)(OR⁴⁶).

In some embodiments, when R³⁶, R³⁷, R³⁸ and R³⁹ are hydrogen, D is —OHand A is —CO₂H then R¹² is not —CO₂H or —OH; when R³⁶, R³⁷, R³⁸ and R³⁹are hydrogen, D is —OH and A is —NH₂ then R¹² is not —CO₂H or CN; whenR³⁶, R³⁸ and R³⁹ are hydrogen, R³⁷ is —OMe, D is —OH and A is —CH₂OHthen R¹² is not —CH₂OH; when R³⁶, R³⁸ and R³⁹ are hydrogen, R³⁷ ishydrogen or methyl, D is —OH and A is —CO₂H then R¹² is not —SH.

In some embodiments, a compound of Formula (XII) is provided:

-   -   wherein:    -   R¹² is —OH, —SH, —CN, —CH₂OH, —CO₂R¹³ or —CONR¹³R¹⁴;    -   D is —SH or —OH;    -   A is —NH₂, —NHCH₃, —N(CH₃)₂, —NHOCH₃, —NOCH₃, —NHC(O)CH₃,        —NHC(O)OCH₃, —NHC(O)NH₂, —NHC(S)NH₂, —NHC(NH)NH₂, —CN, —CH₂OH,        —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H, —CONH₂, —CONHCH₃, or        —CH₂NHC(O)CH₃;    -   R³⁶ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅, —CH(CH₃)₂,        —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁴¹R⁴², —CO₂ ⁴¹, —SO₂NR³⁹R⁴⁰,        —NR³⁹SO₂R⁴⁰, —B(OR³⁹)(OR⁴⁰), —P(O)(OR³⁹)(OR⁴⁰) or        —P(O)(R³⁹)(OR⁴⁰);    -   R³⁷ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅, —CH(CH₃)₂,        —CH₂OH, —CH₂OCH₃, —CN, —C(O)NR⁴³R⁴⁴, —CO₂R⁴³, —SO₂NR⁴³R⁴⁴,        —NR⁴³SO₂R⁴⁴, —B(OR⁴³)(OR⁴⁴), —P(O)(OR⁴³)(OR⁴⁴) or        —P(O)(R⁴³)(OR⁴⁴); and    -   R⁴¹-R⁴⁴ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl or        alternatively R⁴¹ and R⁴² and R⁴³ and R⁴⁴ together with the        atoms to which they are bonded form a cycloheteroalkyl or        substituted cycloheteroalkyl ring. In other embodiments, R¹² is        —OH, —SH, —CN, —CH₂OH or —CO₂H.

In some embodiments, a compound of structural Formula (XIII) isprovided:

-   -   wherein:    -   D is ═O or ═S;    -   A is NH₂, —NHCH₃, —N(CH₃)₂, —NHOCH₃, —NOCH₃, —NHC(O)CH₃,        —NHC(O)OCH₃, —NHC(O)NH₂, —NHC(S)NH₂, —NHC(NH)NH₂, —CN, —CH₂OH,        —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H, —CONH₂, —CONHCH₃, or        —CH₂NHC(O)CH₃;    -   R¹⁷ is alkyl or aryl;    -   R³⁵ is hydrogen, —OH, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅,        —CH(CH₃)₂, chloro, fluoro, —CH₂OH, —CH₂OCH₃, —CN, —NR³⁹R⁴⁰,        —C(O)NR³⁹R⁴⁰, —CO₂R⁴⁰, —SO₂NR³⁹R⁴⁰, —NR³⁹SO₂R⁴⁰, —B(OR³⁹)(OR⁴⁰),        —P(O)(OR³⁹)(OR⁴⁰) or —P(O)(R³⁹)(OR⁴⁰);    -   R³⁶ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —OH, —CH₃, —C₂H₅,        —CH(CH₃)₂, chloro, fluoro, —CH₂OH, —CH₂OCH₃, —CN, —NR⁴¹R⁴¹,        —C(O)NR⁴¹R⁴², —CO₂R⁴¹, —SO₂NR⁴¹R⁴², —NR⁴¹SO₂R⁴², —B(OR⁴¹)(OR⁴²),        —P(O)(OR⁴¹)(OR⁴²) or —P(O)(R⁴¹)(OR⁴²);    -   R³⁷ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —OH, —CH₃, —C₂H₅,        —CH(CH₃)₂, chloro, fluoro, —CH₂OH, —CH₂OCH₃, —CN, —NR⁴³R⁴⁴,        —C(O)NR⁴³R⁴⁴, —CO₂R⁴³, —SO₂NR⁴³R⁴⁴, —NR⁴³SO₂R⁴⁴, —B(OR⁴³)(OR⁴⁴),        —P(O)(OR⁴³)(OR⁴⁴) or —P(O)(R⁴³)(OR⁴⁴);    -   R³⁸ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —OH, —CH₃, —C₂H₅,        —CH(CH₃)₂, chloro, fluoro, —CH₂OH, —CH₂OCH₃, —CN, —NR⁴⁵R⁴⁶,        —C(O)NR⁴⁵R⁴⁶, —CO₂R⁴⁵, —SO₂NR⁴⁵R⁴⁶, —NR⁴⁵SO₂R⁴⁶, —B(OR⁴⁵)(OR⁴⁶),        —P(O)(OR⁴⁵)(OR⁴⁶) or —P(O)(R⁴⁵)(OR⁴⁶); and    -   R³⁹-R⁴⁶ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl or        alternatively R³⁹ and R⁴⁰, R⁴¹ and R⁴², R⁴³ and R⁴⁴ and R⁴⁵ and        R⁴⁶ together with the atoms to which they are bonded form a        cycloheteroalkyl or substituted cycloheteroalkyl ring.

In other embodiments, when A is ═O, A is —NH₂ and R³⁵, R³⁶, R³⁷ and R³⁸are hydrogen then R¹⁷ is not methyl, ethyl or phenyl.

In some embodiments, R³⁵ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃,—C₂H₅, —CH(CH₃)₂, —CH₂OH, —CH₂OCH₃, —CN, —NR³⁹R⁴⁰, —C(O)NR³⁹R⁴⁰,—CO₂R⁴⁰, —SO₂NR³⁹R⁴⁰, —NR³⁹SO₂R⁴⁰, —B(OR³⁹)(OR⁴⁰), —P(O)(OR³⁹)(OR⁴⁰) or—P(O)(R³⁹)(OR⁴⁰), R³⁶ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅,—CH(CH₃)₂, —CH₂OH, —CH₂OCH₃, —CN, —NR⁴¹R⁴¹, —C(O)NR⁴¹R⁴², —CO₂R⁴¹,—SO₂NR⁴¹R⁴², —NR⁴¹SO₂R⁴², —B(OR⁴¹)(OR⁴²), —P(O)(OR⁴¹)(OR⁴²) or—P(O)(R⁴¹)(OR⁴²), R³⁷ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃, —C₂H₅,—CH(CH₃)₂, —CH₂OH, —CH₂OCH₃, —CN, —NR⁴³R⁴⁴, —C(O)NR⁴³R⁴⁴, —CO₂R⁴³,—SO₂NR⁴³R⁴⁴, —NR⁴³SO₂R⁴⁴, —B(OR⁴³)(OR⁴⁴), —P(O)(OR⁴³)(OR⁴⁴) or—P(O)(R⁴³)(OR⁴⁴) and R³⁸ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —CH₃,—C₂H₅, —CH(CH₃)₂, —CH₂OH, —CH₂OCH₃, —CN, —NR⁴⁵R⁴⁶, —C(O)NR⁴⁵R⁴⁶,—CO₂R⁴⁵, —SO₂NR⁴⁵R⁴⁶, —NR⁴⁵SO₂R⁴⁶, —B(OR⁴⁵)(OR⁴⁶), —P(O)(OR⁴⁵)(OR⁴⁶) or—P(O)(R⁴⁵)(OR⁴⁶).

In some embodiments, a compound of structural Formula (XIV) is provided:

-   -   wherein:    -   A is NH₂, —NHCH₃, —N(CH₃)₂, —NHOCH₃, —NOCH₃, —NHC(O)CH₃,        —NHC(O)OCH₃, —NHC(O)NH₂, —NHC(S)NH₂, —NHC(NH)NH₂, —CN, —CH₂OH,        —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H, —CONH₂, —CONHCH₃, or        —CH₂NHC(O)CH₃;    -   R¹⁷ is alkyl or aryl;    -   R³⁶ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —C₂H₅, —CH(CH₃)₂,        —CH₂OH, —CH₂OCH₃, —CN, —NR⁴¹R⁴¹, —C(O)NR⁴¹R⁴², —CO₂R⁴¹,        —SO₂NR³⁹R⁴⁰, —NR³⁹SO₂R⁴⁰, —B(OR³⁹)(OR⁴⁰), —P(O)(OR³⁹)(OR⁴⁰) or        —P(O)(R³⁹)(OR⁴⁰);    -   R³⁷ is hydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, —C₂H₅, —CH(CH₃)₂,        —CH₂OH, —CH₂OCH₃, —CN, —NR⁴³R⁴⁴, —C(O)NR⁴³R⁴⁴, —CO₂R⁴³,        —SO₂NR⁴¹R⁴², —NR⁴¹SO₂R⁴², —B(OR⁴¹)(OR⁴²), —P(O)(OR⁴¹)(OR⁴²) or        —P(O)(R⁴¹)(OR⁴²); and    -   R⁴¹-R⁴³ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively R⁴¹ and R⁴² and R⁴³        and R⁴⁴ together with the atoms to which they are bonded form a        cycloheteroalkyl or substituted cycloheteroalkyl ring. In some        embodiments, when R³⁶ and R³⁷ are methyl, D is ═O and A is —NH₂,        then R¹⁷ is not methyl.

In some embodiments, compounds having the structures below are provided:

In other embodiments, compounds having the structures below areprovided:

In still other embodiments, compounds having the structures below areprovided:

In still other embodiments, a compound having the structure below isprovided:

In still other embodiments, compounds having the structures below areprovided:

In some embodiments, compounds having the structure below are provided:

In still other embodiments, a compound having the structure below isprovided:

In still other embodiments, a compound having the structure below isprovided:

In some embodiments, a compound having the structure below is provided:

In still other embodiments, compounds having the structures below areprovided:

In some embodiments, compounds of structural formula (XV) below areprovided:

-   -   wherein:    -   D is —SH or —OH; and    -   A is —OH, —NH₂, —NHCH₃, —N(CH₃)₂, —NHOCH₃, —NOCH₃, —NHC(O)CH₃,        —NHC(O)OCH₃, —NHC(O)NH₂, —NHC(S)NH₂, —NHC(NH)NH₂, —CN, —CH₂OH,        —CH₂NH₂, —CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H, —CONH₂, —CONHCH₃, or        —CH₂NHC(O)CH₃;    -   provided that at least one of L, M, T or R is a heteroatom.

In some embodiments, when p is 0, L is —NH—, M is —CH(CH₂OEt),

R is

X is hydrogen, chloro or methoxy, A is —NH₂ then D is not —SH;

-   -   when p is 0, L is —CH₂—, M is —NCH₃—, R is —C(CH₃)₂—, A is —NH₂,        then D is not —SH or —OH;    -   when p is 0, L is —NH—, M is —CH(CH₂OH)—, R is

X is hydrogen or methoxy, A is —NH₂ then D is not —SH;

-   -   when p is 0, L is —NH—, M is —CH(CH₃)—, R is

A is —NH₂ then D is not —SH;

-   -   L is —S—, M, R and T are —CH₂—, A is —NH₂ then D is not —OH;    -   L is —NH—, M and T are —CH₂—, R is —CH(CH₃)—, A is —NH₂ then D        is not —OH;    -   and M is —N(COPh)—, L, R and T are —CH₂—, A is —NH₂ then D is        not —OH.

In some embodiments, compounds having the structures below are provided:

In other embodiments, compounds having the structure below are provided:

In some aspects, a compound of structural Formula (XVI) is provided:

-   -   or a salt, solvate, hydrate or N-oxide thereof wherein:    -   each G is independently —C(R⁷⁷)(R⁷⁸)—, —C(O)—, —NR⁷⁷— or        —S(O)₂—;    -   n is 1, 2 or 3;    -   provided that when n is greater than one then only one G is        —C(O)—, —C(S), —S(O)₂— or —NR⁷⁷—;    -   Y is —C(O)—, —C(S) or —S(O)₂—;    -   R⁷⁰ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN,        —NO₂, —OR⁷², —S(O)_(a)R⁷², —NR⁷²R⁷³, —CONR⁷²R⁷³, —CO₂R⁷²,        —NR⁷²CO₂R⁷³, —NR⁷²CONR⁷³R⁷⁴, —NR⁷²CSNR⁷³R⁷⁴ or        —NR⁷²C(═NH)NR⁷³R⁷⁴, —SO₂NR⁷²R⁷³, —NR⁷²SO₂R⁷³, —NR⁷²SO₂NR⁷³R⁷⁴,        —B(OR⁷²)(OR⁷³), —P(O)(OR⁷²)(OR⁷³) or —P(O)(R⁷²)(OR⁷³);    -   a and b are independently 0, 1 or 2;    -   R⁷¹ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN,        —NO₂, —OR⁷⁴, —S(O)_(b)R⁷⁴, —NR⁷⁴R⁷⁵, —CONR⁷⁴R⁷⁵, —CO₂R⁷⁴,        —NR⁷⁴CO₂R⁷⁵, —NR⁷⁴CONR⁷⁵R⁷⁶, —NR⁷⁴CSNR⁷⁵R⁷⁶ or        —NR⁷⁴C(═NH)NR⁷⁵R⁷⁶, —SO₂NR⁷⁴R⁷⁵, —NR⁷⁴SO₂R⁷⁵, —NR⁷⁴SO₂NR⁷⁵R⁷⁶,        —B(OR⁷⁴)(OR⁷⁵), —P(O)(OR⁷⁴)(OR⁷⁵), —P(O)(R⁷⁴)(OR⁷⁵) or        alternatively, R⁷¹ and R⁷² together with the atoms to which they        are bonded form an aryl, substituted aryl, heteroaryl,        substituted heteroaryl, cycloalkyl, substituted cycloalkyl,        cycloheteroalkyl or substituted cycloheteroalkyl ring where the        ring is optionally fused to another aryl, substituted aryl,        heteroaryl, substituted heteroaryl, cycloalkyl, substituted        cycloalkyl, cycloheteroalkyl or substituted cycloheteroalkyl        ring;    -   R⁷²-R⁷⁶ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively, R⁷² and R⁷³, R⁷³        and R⁷⁴, R⁷⁴ and R⁷⁵ and R⁷⁵ and R⁷⁶ together with the atoms to        which they are bonded form a cycloheteroalkyl or substituted        cycloheteroalkyl ring; and    -   R⁷⁷-R⁷⁸ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively, R⁷⁷ and R⁷⁸,        together with the atoms to which they are bonded form a        cycloalkyl, substituted cycloalkyl, cycloheteroalkyl or        substituted cycloheteroalkyl ring.

In some embodiments, when G is —C(O)— and R⁷⁸ is hydrogen, R⁷¹ and R⁷²do not form a phenyl ring. In other embodiments, R⁷⁰ and R⁷¹ togetherwith the atoms to which they are bonded form an aryl, substituted aryl,heteroaryl, substituted heteroaryl, cycloalkyl, substituted cycloalkyl,cycloheteroalkyl or substituted cycloheteroalkyl ring where the ring isoptionally fused to another aryl, substituted aryl, heteroaryl,substituted heteroaryl, cycloalkyl, substituted cycloalkyl,cycloheteroalkyl or substituted cycloheteroalkyl ring.

In still other embodiments, a compound of structural formula (XVII),(XVIII), (XIX) or (XX) is provided:

-   -   where o is 1 or 2.

In some embodiments, R⁷⁰ and R⁷¹ together with the atoms to which theyare bonded form an aryl, substituted aryl, heteroaryl, substitutedheteroaryl, cycloalkyl, substituted cycloalkyl, cycloheteroalkyl orsubstituted cycloheteroalkyl ring where the ring is optionally fused toanother aryl, substituted aryl, heteroaryl, substituted heteroaryl,cycloalkyl, substituted cycloalkyl, cycloheteroalkyl or substitutedcycloheteroalkyl ring.

In still other embodiments, a compound of structural formula (XXI) isprovided:

-   -   wherein:    -   X is O or S;    -   H is —N— or —CR⁸¹—;    -   I is —N— or —CR⁸²—;    -   J is —N— or —CR⁸³—;    -   K is —N— or —CR⁸⁴—;    -   with the proviso that no more than 2 of H, I, J or K are —N—;    -   R⁸¹ is hydrogen, alkoxy, —OCH₃, —OC₂H₅, —OC₃H₇, alkyl, —CH₃,        —C₂H₅, —CH(CH₃)₂, —CH₂OH, halo, chloro, fluoro, —CH₂OCH₃, —CN,        —C(O)NR⁸⁵R⁸⁶, —CO₂R⁸⁵, —SO₂NR⁸⁵R⁸⁶, —NR⁸⁵SO₂R⁸⁶, —B(OR⁸⁵)(OR⁸⁶),        —P(O)(OR⁸⁵)(OR⁸⁶) or —P(O)(R⁸⁵)(OR⁸⁶);    -   R⁸² is hydrogen, alkoxy, —OCH₃, —OC₂H₅, —OC₃H₇, alkyl, —CH₃,        —C₂H₅, —CH(CH₃)₂, —CH₂OH, halo, chloro, fluoro, —CH₂OCH₃, —CN,        —C(O)NR⁸⁶R⁸⁷, —CO₂R⁸⁶, —SO₂NR⁸⁶R⁸⁷, —NR⁸⁶SO₂R⁸⁷, —B(OR⁸⁶)(OR⁸⁷),        —P(O)(OR⁸⁶)(OR⁸⁷) or —P(O)(R⁸⁶)(OR⁸⁷);    -   R⁸³ is hydrogen, alkoxy, —OCH₃, —OC₂H₅, —OC₃H₇, alkyl, —CH₃,        —C₂H₅, —CH(CH₃)₂, —CH₂OH, halo, chloro, fluoro, —CH₂OCH₃, —CN,        —C(O)NR⁸⁸R⁸⁹, —CO₂R⁸⁸, —SO₂NR⁸⁸R⁸⁹, —NR⁸⁸SO₂R⁸⁹, —B(OR⁸⁸)(OR⁸⁹),        —P(O)(OR⁸⁸)(OR⁸⁹) or —P(O)(R⁸⁸)(OR⁸⁹);    -   R⁸⁴ is hydrogen, alkoxy, —OCH₃, —OC₂H₅, —OC₃H₇, alkyl, —CH₃,        —C₂H₅, —CH(CH₃)₂, —CH₂OH, halo, chloro, fluoro, —CH₂OCH₃, —CN,        —C(O)NR⁹⁰R⁹¹, —CO₂R⁹⁰, —SO₂NR⁹⁰R⁹¹, —NR⁹⁰SO₂R⁹¹, —B(OR⁹⁰)(OR⁹¹),        —P(O)(OR⁹⁰)(OR⁹¹) or —P(O)(R⁹⁰)(OR⁹¹); and    -   R⁸⁵-R⁹¹ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively R⁸⁵ and R⁸⁶, R⁸⁷        and R⁸⁸, R⁸⁹ and R⁹⁰ and R⁹¹ and R⁹² together with the atoms to        which they are bonded form a cycloalkyl, substituted cycloalkyl,        cycloheteroalkyl or substituted cycloheteroalkyl ring;    -   provided that R⁸¹, R⁸², R⁸³ and R⁸⁴ are not all hydrogen.

In some embodiments, R⁸¹, R⁸², R⁸³ and R⁸⁴ are independently hydrogen,alkoxy, —OCH₃, —OC₂H₅, —OC₃H₇, alkyl, —CH₃, —C₂H₅, —CH(CH₃)₂, —CH₂OH,halo, chloro, fluoro, —CH₂OCH₃, —CN, —C(O)NHMe, —CO₂H, —CO₂CH₃,—SO₂N(CH₃)₂, —NHSO₂CH₃, —B(OH)₂ or —P(O)(OH)₂.

In still other embodiments, compounds having the structures below areprovided:

In still another aspect, a compound of structural Formula (XXII) isprovided:

-   -   or a salt, solvate, hydrate or N-oxide thereof wherein:    -   each G is independently —C(R⁹⁴)(R⁹⁵)—, —C(O)—, —NR⁹⁴— or        —S(O)₂—;    -   n is 1, 2 or 3;    -   provided that when n is greater than one then only one G is        —C(O)—, —S(O)₂— or —NR⁹⁴—;    -   Y is —C(O)—, —C(S)— or —S(O)₂—;    -   L is —C(R¹⁰⁴)(R¹⁰⁵)—, —O—, or —NR¹⁰⁴—;    -   R⁹² is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN,        —NO₂, —OR⁹⁸, —S(O)_(y)R⁹⁸, —NR⁹⁸R⁹⁹, —CONR⁹⁸R⁹⁹, —CO₂R⁹⁸,        —NR⁹⁸CO₂R⁹⁹, —NR⁹⁸CONR⁹⁹R¹⁰⁰, —NR⁹⁸CSNR⁹⁹R¹⁰⁰ or        —NR⁹⁸C(═NH)NR⁹⁹R¹⁰⁰, —SO₂NR⁹⁸R⁹⁹, —NR⁹⁸SO₂R⁹⁹, —NR⁹⁸SO₂NR⁹⁹R¹⁰⁰,        —B(OR⁹⁸)(OR⁹⁹), —P(O)(OR⁹⁸)(OR⁹⁹) or —P(O)(R⁹⁸)(OR⁹⁹);    -   R⁹³ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl, substituted heteroarylalkyl, —CN,        —NO₂, —OR¹⁰⁰, —S(O)_(z)R¹⁰¹, —NR¹⁰¹R¹⁰², —CONR¹⁰¹R¹⁰², —CO₂R¹⁰¹,        —NR¹⁰¹CO₂R¹⁰², —NR¹⁰¹CONR¹⁰²R¹⁰³, —NR¹⁰¹CSNR¹⁰²R¹⁰³ or        —NR¹⁰¹C(═NH)NR¹⁰²R¹⁰³, —SO₂NR¹⁰¹R¹⁰², —NR¹⁰¹SO₂NR¹⁰²,        —NR¹⁰¹SO₂R¹⁰²R¹⁰³, —B(OR¹⁰¹)(OR¹⁰²), —P(O)(OR¹⁰¹)(OR¹⁰²),        —P(O)(R¹⁰¹)(OR¹⁰²) or alternatively, R⁹² and R⁹³ together with        the atoms to which they are bonded form an aryl, substituted        aryl, heteroaryl, substituted heteroaryl, cycloalkyl,        substituted cycloalkyl, cycloheteroalkyl or substituted        cycloheteroalkyl ring where the ring is optionally fused to        another aryl, substituted aryl, heteroaryl, substituted        heteroaryl, cycloalkyl, substituted cycloalkyl, cycloheteroalkyl        or substituted cycloheteroalkyl ring;    -   y and z are independently 0, 1 or 2;    -   R⁹⁸-R¹⁰³ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively, R⁹⁸ and R⁹⁹, R⁹⁹        and R¹⁰⁰, R¹⁰¹ and R¹⁰² and R¹⁰¹ and R¹⁰² together with the        atoms to which they are bonded form a cycloalkyl, substituted        cycloalkyl, cycloheteroalkyl or substituted cycloheteroalkyl        ring;    -   R⁹⁴-R⁹⁵ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively, R⁹⁴ and R⁹⁵,        together with the atoms to which they are bonded form a        cycloalkyl, substituted cycloalkyl, cycloheteroalkyl or        substituted cycloheteroalkyl ring;    -   R⁹⁶ is hydrogen, alkyl, substituted alkyl, aryl, substituted        aryl, arylalkyl, substituted arylalkyl, acyl, substituted acyl,        heteroalkyl, substituted heteroalkyl, heteroaryl, substituted        heteroaryl, heteroarylalkyl or substituted heteroarylalkyl; and    -   R¹⁰⁴-R¹⁰⁵ are independently hydrogen, alkyl, substituted alkyl,        aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,        substituted acyl, heteroalkyl, substituted heteroalkyl,        heteroaryl, substituted heteroaryl, heteroarylalkyl or        substituted heteroarylalkyl or alternatively, R¹⁰⁴ and R¹⁰⁵,        together with the atoms to which they are bonded form a        cycloalkyl, substituted cycloalkyl, cycloheteroalkyl or        substituted cycloheteroalkyl ring.

In some embodiments, when L is O, R⁹⁵ is hydrogen, R⁹² is methyl and thebond connecting the carbon atoms bonded to R⁹² and R⁹³ is a double bondthen R⁹³ is not hydrogen.

In some embodiments, a compound of structural formula (XXIII) isprovided:

-   -   where when R⁹² is —CH₃ then R⁹³ is not hydrogen and that both        R⁹² and R⁹³ are not hydrogen.

In some embodiments, R⁹² and R⁹³ are independently are independentlyhydrogen, —OCH₃, —OC₂H₅, —OC₃H₇, alkyl, —CH₃, —C₂H₅, —CH(CH₃)₂, —CH₂OH,halo, chloro, fluoro, —CH₂OCH₃, —CN, —SCH₃, —C(O)NHMe, —CO₂H, —CO₂CH₃,—SO₂N(CH₃)₂, —NHSO₂CH₃, —B(OH)₂ or —P(O)(OH)₂. In other embodiments, R⁹²and R⁹³ together with the atoms to which they are attached form acycloalkyl, cycloheteroalkyl, aryl or heteroaryl ring.

In other embodiments, compounds having the structures below areprovided:

In general, the compounds of the present invention, e.g., compounds withthe formulae described herein can be synthesized according to thefollowing exemplary procedures and/or schemes.

Pyrimidines B including fused pyrimidine derivatives such asquinazolines and pyrido[2,3-d]pyrimidines are synthesized from 2-aminonitriles, 2-amino ketones, or 2-amino carboxyl derivatives A by reactionwith the corresponding carboxyl derivatives as illustrated in Scheme 1(Rad-Moghadam et al., J. of Heterocyclic Chem. 2006, 43, 913; Roy etal., J. Org. Chem. 2006, 71, 382; Jung et al., J. Med. Chem. 2006, 49,955; Khabnadideh et al., Bioorg. Med. Chem. 2005, 13, 2637). The aminogroup in the starting material A can be further functionalized byalkylation (Brown et al., J. Med. Chem. 1990, 33, 1771) or reductiveamination (Uehling et al., J. Med. Chem. 2006, 49, 2758, etc.) toprovide the corresponding N-monosubstituted 2-amino nitriles, 2-aminoketones or 2-amino carboxyl derivatives C. The coupling reaction of A orC with iso(thio)cyanates such as, for example, benzoyliso(thio)cyanatesand subsequent cyclization by treatment with NaOH provides thepyrimidin-2(1H)-(thi)one derivatives E including, but not limited to,fused pyrimidin-2(1H)-(thi)ones such as quinazolin-2(1H)-(thi)one andpyrido[2,3-d]pyrimidin-2(1H)-(thi)one derivatives (El-Sherbeny et al.,Med. Chem. Rev. 2000, 10, 122 and references cited therein; Reddy etal., Synthetic Commun. 1988, 18, 525; Wilson, Org. Lett. 2001, 3, 585,and references cited therein). Direct cyclization of A or C with(thio)ureas in the presence of NaOH also results in the formation ofpyrimidin-2(1H)-(thi)one derivatives E (Scheme 1) (Naganawa et al.,Bioorg. Med. Chem. 2006, 14, 7121 and references cited therein).

Pyrimidines B and pyrimidin-2(1H)-(thi)ones E can also be prepared fromcorresponding 1,3-dicarbonyl derivatives and α,β-unsaturated carbonylderivatives by condensation with guanidines, amidines, or (thio)ureaderivatives as shown in Scheme 2 (Sharma et al., Eur. J. Med. Chem.2006, 41, 83, and references cited therein; Bellur et al., Tetrahedron2006, 62, 5426 and references cited therein; Hauser et al., J. Org.Chem. 1953, 18, 588).

Various pyrimidines and pyrimidin-2(1H)-(thi)ones as well as their fusedpyrimidine and pyrimidin-2(1H)-(thi)one derivatives such as quinazolinesand quinazolin-2(1H)-ones can be synthesized frompyrimidine-2,4(1H,3H)-dione derivatives as well as the fusedpyrimidine-2,4(1H,3H)-diones such as quinazoline-2,4(1H,3H)-dione andpyrido[2,3-d]pyrimidine-2,4(1H,3H)-dione derivatives (Scheme 3).Reaction of pyrimidine-2,4(1H,3H)-dione derivatives with phosgene orPOCl₃ provides the corresponding 2,4-dichloropyrimidines (Lee et al.,Synlett. 2006, 65 and references cited therein). Subsequentdisplacements of the two chlorides with various nucleophiles resulted inthe formation of pyrimidines and pyrimidin-2(1H)-(thi)ones as well asfused pyrimidine and pyrimidin-2(1H)-(thi)one derivatives (Kanuma etal., Bioorg. & Med. Chem. Lett. 2005, 15, 3853 and references citedtherein; Liu et al., Bioorg. & Med. Chem. Lett. 2007, 17, 668; Wilson etal., Bioorg. & Med. Chem. 2007, 15, 77; Boarland et al., J. Chem. Soc.1951, 1218).

Similarly, [1,2,6]thiadiazine-2,2-dioxides andfused[1,2,6]thiadiazine-2,2-dioxide derivatives such as, for example,1H-benzo[c][1,2,6]thiadiazine-2,2-dioxides are also synthesized from2-amino nitriles, 2-amino ketones, or 2-amino carboxyl derivatives A orC (Scheme 4), by reaction with NH₂SO₂Cl (Hirayama et al., Bioorg. & Med.Chem. 2002, 10, 1509; Kanbe et al., Bioorg. & Med. Chem. Lett. 2006, 16,4090 and references cited therein) or NH₂SO₂NH₂ (Maryanoff et al., J.Med. Chem. 2006, 49, 3496, and references cited therein) and followed bycyclization in the presence of NaOH (Goya et al., Heterocycles, 1986,24, 3451; Albrecht et al., J. Org. Chem. 1979, 44, 4191; Goya et al.,Arch. Pharm. (Weinheim) 1984, 317, 777). The condensation of thecorresponding 1,3-dicarbonyl derivatives, α,β-unsaturated carbonylderivatives with sulfamide derivatives (Scheme 4) also results in theformation of [1,2,6]thiadiazine-2,2-dioxide derivatives (Wright, J. Org.Chem. 1964, 29, 1905).

Methods for the synthesis of thieno[2,3-d]pyrimidine derivatives aredescribed in Scheme 5. 2-Amino thiophene derivatives 303 are synthesizedvia the Gewald reaction (Chen et al., Synthetic Communication 2004, 34,3801 and references cited therein; Elmegeed et al., Eur. J. Med. Chem.2005, 40, 1283 and references cited therein). Compound 303 can becyclized with the corresponding carboxyl derivatives to give thethieno[2,3-d]pyrimidine derivatives 304 (Rad-Moghadam, J. HeterocyclicChem. 2006, 43, 913; Seijas et al., Tetrahedron Lett. 2000, 41, 2215,and references cited therein; Jung et al., J. Med. Chem. 2006, 49,955.).

2-Amino thiophene derivatives 303 can be further alkylated by eithertreatment with R₃Br/K₂CO₃ or with RCHO/NaBH(OAc)₃ to give theN-alkylated 2-amino thiophene derivatives 305 (Brown et al., J. Med.Chem. 1990, 33, 1771; Uehling et al., J. Med. Chem. 2006, 49, 2758 andreferences cited therein), which are then reacted, for example, withbenzoyliso(thio)cyanate to give the corresponding benzoyl(thio)ureaderivatives 306. Compounds 306 may be cyclized by treatment with NaOH toprovide thieno[2,3-d]pyrimidine derivatives 7 (El-Sherbeny et al., Med.Chem. Rev. 2000, 10, 122, and references cited therein; Reddy et al.,Synthetic Commun. 1988, 18, 525; Wilson, Org. Lett. 2001, 3, 585 andreferences cited therein). When R³═H, compounds 307 may be reacted withR₅Br/NaOH to give the alkylated products 8 (Hirota et al., Bioorg. Med.Chem. 2003, 11, 2715.). When R⁴═NH₂, the amino group can be furtherfunctionalized to give the products 309.

Similarly, quinazolin-2(1H)-one and quinazolin-2(1H)-thione derivatives402 were synthesized from various 2-aminobenzoic acid derivatives,2-aminobenzonitrile derivatives, 2-aminoacetophenone derivatives and2-aminobenzamide derivatives 400 as shown in Scheme 6. Coupling reactionof compounds 400 with benzoyl iso(thio)cyanates lead to the formation ofcorresponding benzoyl(thio)urea derivatives 401. Their cyclization inthe presence of NaOH provides the quinazolin-2(1H)-(thi)one derivatives402 (El-Sherbeny, Med. Chem. Rev. 2000, 10, 122 and references citedtherein; Reddy et al., Synthetic Commun. 1988, 18, 525; Wilson, Org.Lett. 2001, 3, 585 and references cited therein).

1H-benzo[c][1,2,6]thiadiazine-2,2-dioxide derivatives 404 aresynthesized from the same starting materials 400 (Scheme 7) via theirreactions with sulfamide or sulfamoyl chloride, followed by cyclizationwith NaOH. Direct reaction of compounds 400 with sulfamide in thepresence of DBU at the elevated temperature also resulted in theformation of 1H-benzo[c][1,2,6]thiadiazine-2,2-dioxide derivatives 404(Maryanoff et al., J. Med. Chem. 2006, 49, 3496, and references citedtherein).

Quinazoline derivatives are also synthesized fromquinazoline-2,4(1H,3H)-diones (Scheme 8). Reaction ofquinazoline-2,4(1H,3H)-diones with POCl₃ provided the correspondingdichloroquinazolines (Zunszain et al., Bioorg. & Med. Chem. 2005, 13,3681 and references cited therein). Subsequent displacements of the twochlorides with various nucleophiles resulted in formation of quinazolinederivatives (Scheme 8) (Kanuma et al., Bioorg. & Med. Chem. Lett. 2005,15, 3853 and references cited therein; Blackburn, Bioorg. & Med. Chem.Lett. 2006, 16, 2621).

4-Amino-5,6,7,8-tetrahydroquinazolin-2(1H)-(thi)one derivatives and4-amino-5,6,7,8-tetrahydro-1H-benzo[c][1,2,6]thiadiazine-2,2-dioxidederivatives, as well as structural analogs with different ring sizes, asshown in Scheme 9, are generally synthesized according to the methodsdescribed therein. Thorpe-Ziegler cyclization of dinitriles in thepresence of base provides β-amino-α,β-unsaturated nitrile derivatives(Winkler et al., Tetrahedron 2005, 61, 4249; Yoshizawa et al., GreenChem. 2002, 4, 68, and references cited therein; Rodriguez-Hahn et al.,Synthetic Commun. 1984, 14, 967, and references cited therein; Franciset al., J. Med. Chem. 1991, 34, 2899). The β-amino-α,β-unsaturatednitriles may be reacted, for example, with benzoyliso(thio)cyanate andsubsequently cyclized by treatment with NaOH to provide4-amino-5,6,7,8-tetrahydroquinazolin-2(1H)-(thi)one derivatives(El-Sherbeny et al., Med. Chem. Rev. 2000, 10, 122, and references citedtherein; Reddy et al., Synthetic Commun. 1988, 18, 525) as well as theirstructural analogs with different ring sizes (Scheme 9). Similarlyreaction of β-amino-α,β-unsaturated nitrile derivatives with sulfamoylchloride, followed by treatment with NaOH provides4-amino-5,6,7,8-tetrahydro-1H-benzo[c][1,2,6]thiadiazine-2,2-dioxidederivatives, as well as structural analogs with different ring size(Scheme 9) (Hirayama et al., Bioorg. & Med. Chem. 2002, 10, 1509; Kanbeet al., Bioorg. & Med. Chem. Lett. 2006, 16, 4090 and references citedtherein).

Acesulfame and fused acesulfame derivatives C such asbenzo[e][1,2,3]oxathiazin-4(3H)-one-2,2-dioxides can be synthesized viathe reaction of 1,3-dicarbonyl derivatives A or 2-hydroxy carboxylderivatives B and D with SO₃ or ClSO₂NH₂, as described in Scheme 10(Linkies et al, Synthesis 1990, 405 and references cited therein; Ahmedet al., J. Org. Chem. 1988, 53, 4112; Ahmed et al., Heterocycles 1989,29, 1391).

Acesulfame derivatives C can also be synthesized via cyclization ofalkynes or enols with FSO₂NCO (Clauss et al., Tetrahedron Lett. 1970, 2,119) or ClSO₂NCO (Rasmussen et al., J. Org. Chem. 1973, 38, 2114; Etteret al., J. Org. Chem. 1986, 51, 5405; Tripathi et al., Indian J. Chem.Sect. B 1987, 26B, 1082.) as shown in Scheme 11.

Saccharin derivatives may be synthesized by direct oxidative cyclizationof N-alkyl-o-methyl-arenesulfonamides as shown in Scheme 12 (Xu et al.,Tetrahedron 2006, 62, 7902 and references cited therein; Pal et al.,Letters in Drug Design & Discovery 2005, 2, 329). Cyclization ofo-carboxyl-arenesulfonyl chloride derivatives with primary amines canalso provide saccharin derivatives (Robinson et al., Eur. J. Org. Chem.2006, 19, 4483 and references cited therein; Yamada et al., J. Med.Chem. 2005, 48, 7457 and references cited therein; Da Settimo et al., J.Med. Chem. 2005, 48, 6897). Other heteroaromatic fusedisothiazol-3(2H)-one-1,1-dioxide derivatives may be synthesizedsimilarly.

According to the present invention, chemosensory receptor modifiers orchemosensory receptor ligand modifiers of the present invention can beused for one or more methods of the present invention, e.g., modulatinga chemosensory receptor and/or its ligands. In general, chemosensoryreceptor modifiers and chemosensory receptor ligand modifiers of thepresent invention are provided in a composition, e.g., pharmaceutical,medicinal or comestible composition, or alternatively in a formulation,e.g., a pharmaceutical or medicinal formulation or a food or beverageproduct or formulation.

In one embodiment, the chemosensory receptor modifiers or chemosensoryreceptor ligand modifiers provided by the present invention can be usedat very low concentrations on the order of a few parts per million, incombination with one or more known sweeteners, natural or artificial, soas to reduce the concentration of the known sweetener required toprepare a comestible composition having the desired degree of sweetness.

Commonly used known or artificial sweeteners for use in suchcombinations of sweeteners include but are not limited to the commonsaccharide sweeteners, e.g., sucrose, fructose, glucose, and sweetenercompositions comprising those natural sugars, such as corn syrup orother syrups or sweetener concentrates derived from natural fruit andvegetable sources, or semi-synthetic “sugar alcohol” sweeteners such aserythritol, isomalt, lactitol, mannitol, sorbitol, xylitol,maltodextrin, and the like, or well known artificial sweeteners such asaspartame, saccharin, acesulfame-K, cyclamate, sucralose, and alitame;or any mixture thereof.

Chemosensory receptor modifiers and chemosensory receptor ligandmodifiers of the present invention can also be provided, individually orin combination, with any comestible composition known or laterdiscovered. A variety of classes, subclasses and species of comestiblecompositions are known. Exemplary comestible compositions include one ormore confectioneries, chocolate confectionery, tablets, countlines,bagged selflines/softlines, boxed assortments, standard boxedassortments, twist wrapped miniatures, seasonal chocolate, chocolatewith toys, alfajores, other chocolate confectionery, mints, standardmints, power mints, boiled sweets, pastilles, gums, jellies and chews,toffees, caramels and nougat, medicated confectionery, lollipops,liquorice, other sugar confectionery, gum, chewing gum, sugarized gum,sugar-free gum, functional gum, bubble gum, bread, packaged/industrialbread, unpackaged/artisanal bread, pastries, cakes, packaged/industrialcakes, unpackaged/artisanal cakes, cookies, chocolate coated biscuits,sandwich biscuits, filled biscuits, savory biscuits and crackers, breadsubstitutes, breakfast cereals, rte cereals, family breakfast cereals,flakes, muesli, other cereals, children's breakfast cereals, hotcereals, ice cream, impulse ice cream, single portion dairy ice cream,single portion water ice cream, multi-pack dairy ice cream, multi-packwater ice cream, take-home ice cream, take-home dairy ice cream, icecream desserts, bulk ice cream, take-home water ice cream, frozenyoghurt, artisanal ice cream, dairy products, milk, fresh/pasteurizedmilk, full fat fresh/pasteurized milk, semi skimmed fresh/pasteurizedmilk, long-life/uht milk, full fat long life/uht milk, semi skimmed longlife/uht milk, fat-free long life/uht milk, goat milk,condensed/evaporated milk, plain condensed/evaporated milk, flavored,functional and other condensed milk, flavored milk drinks, dairy onlyflavored milk drinks, flavored milk drinks with fruit juice, soy milk,sour milk drinks, fermented dairy drinks, coffee whiteners, powder milk,flavored powder milk drinks, cream, cheese, processed cheese, spreadableprocessed cheese, unspreadable processed cheese, unprocessed cheese,spreadable unprocessed cheese, hard cheese, packaged hard cheese,unpackaged hard cheese, yoghurt, plain/natural yoghurt, flavoredyoghurt, fruited yoghurt, probiotic yoghurt, drinking yoghurt, regulardrinking yoghurt, probiotic drinking yoghurt, chilled and shelf-stabledesserts, dairy-based desserts, soy-based desserts, chilled snacks,fromage frais and quark, plain fromage frais and quark, flavored fromagefrais and quark, savory fromage frais and quark, sweet and savorysnacks, fruit snacks, chips/crisps, extruded snacks, tortilla/cornchips, popcorn, pretzels, nuts, other sweet and savory snacks, snackbars, granola bars, breakfast bars, energy bars, fruit bars, other snackbars, meal replacement products, slimming products, convalescencedrinks, ready meals, canned ready meals, frozen ready meals, dried readymeals, chilled ready meals, dinner mixes, frozen pizza, chilled pizza,soup, canned soup, dehydrated soup, instant soup, chilled soup, hotsoup, frozen soup, pasta, canned pasta, dried pasta, chilled/freshpasta, noodles, plain noodles, instant noodles, cups/bowl instantnoodles, pouch instant noodles, chilled noodles, snack noodles, cannedfood, canned meat and meat products, canned fish/seafood, cannedvegetables, canned tomatoes, canned beans, canned fruit, canned readymeals, canned soup, canned pasta, other canned foods, frozen food,frozen processed red meat, frozen processed poultry, frozen processedfish/seafood, frozen processed vegetables, frozen meat substitutes,frozen potatoes, oven baked potato chips, other oven baked potatoproducts, non-oven frozen potatoes, frozen bakery products, frozendesserts, frozen ready meals, frozen pizza, frozen soup, frozen noodles,other frozen food, dried food, dessert mixes, dried ready meals,dehydrated soup, instant soup, dried pasta, plain noodles, instantnoodles, cups/bowl instant noodles, pouch instant noodles, chilled food,chilled processed meats, chilled fish/seafood products, chilledprocessed fish, chilled coated fish, chilled smoked fish, chilled lunchkit, chilled ready meals, chilled pizza, chilled soup, chilled/freshpasta, chilled noodles, oils and fats, olive oil, vegetable and seedoil, cooking fats, butter, margarine, spreadable oils and fats,functional spreadable oils and fats, sauces, dressings and condiments,tomato pastes and purees, bouillon/stock cubes, stock cubes, gravygranules, liquid stocks and fonds, herbs and spices, fermented sauces,soy based sauces, pasta sauces, wet sauces, dry sauces/powder mixes,ketchup, mayonnaise, regular mayonnaise, mustard, salad dressings,regular salad dressings, low fat salad dressings, vinaigrettes, dips,pickled products, other sauces, dressings and condiments, baby food,milk formula, standard milk formula, follow-on milk formula, toddlermilk formula, hypoallergenic milk formula, prepared baby food, driedbaby food, other baby food, spreads, jams and preserves, honey,chocolate spreads, nut-based spreads, and yeast-based spreads.

Exemplary comestible compositions also include confectioneries, bakeryproducts, ice creams, dairy products, sweet and savory snacks, snackbars, meal replacement products, ready meals, soups, pastas, noodles,canned foods, frozen foods, dried foods, chilled foods, oils and fats,baby foods, or spreads or a mixture thereof.

Exemplary comestible compositions also include ice creams, breakfastcereals, sweet beverages or solid or liquid concentrate compositions forpreparing beverages, ideally so as to enable the reduction inconcentration of previously known saccharide sweeteners, or artificialsweeteners.

In another embodiment, the chemosensory receptor modifiers andchemosensory receptor ligand modifiers are added to food or beverageproducts or formulations. Examples of food and beverage products orformulations include any entity described in the Wet Soup Category, theDehydrated and Culinary Food Category, the Beverage Category, the FrozenFood Category, the Snack Food Category, and seasonings or seasoningblends.

In general, “Wet Soup Category” usually means wet/liquid soupsregardless of concentration or container, including frozen Soups. Forthe purpose of this definition soup(s) means a food prepared from meat,poultry, fish, vegetables, grains, fruit and other ingredients, cookedin a liquid which may include visible pieces of some or all of theseingredients. It may be clear (as a broth) or thick (as a chowder),smooth, pureed or chunky, ready-to-serve, semi-condensed or condensedand may be served hot or cold, as a first course or as the main courseof a meal or as a between meal snack (sipped like a beverage). Soup maybe used as an ingredient for preparing other meal components and mayrange from broths (consomme) to sauces (cream or cheese-based soups).

“Dehydrated and Culinary Food Category” usually means: (i) Cooking aidproducts such as: powders, granules, pastes, concentrated liquidproducts, including concentrated bouillon, bouillon and bouillon likeproducts in pressed cubes, tablets or powder or granulated form, whichare sold separately as a finished product or as an ingredient within aproduct, sauces and recipe mixes (regardless of technology); (ii) Mealsolutions products such as: dehydrated and freeze dried soups, includingdehydrated soup mixes, dehydrated instant soups, dehydratedready-to-cook soups, dehydrated or ambient preparations of ready-madedishes, meals and single serve entrees including pasta, potato and ricedishes; and (iii) Meal embellishment products such as: condiments,marinades, salad dressings, salad toppings, dips, breading, battermixes, shelf stable spreads, barbecue sauces, liquid recipe mixes,concentrates, sauces or sauce mixes, including recipe mixes for salad,sold as a finished product or as an ingredient within a product, whetherdehydrated, liquid or frozen.

“Beverage Category” usually means beverages, beverage mixes andconcentrates, including but not limited to, alcoholic and non-alcoholic,ready to drink beverages, liquid concentrate formulations for preparingbeverages such as sodas, and dry powdered beverage precursor mixes.

Other examples of food and beverage products or formulations includecarbonated and non-carbonated beverages, e.g., sodas, fruit or vegetablejuices, alcoholic and non-alcoholic beverages, confectionery products,e.g., cakes, cookies, pies, candies, chewing gums, gelatins, ice creams,sorbets, puddings, jams, jellies, salad dressings, and other condiments,cereal, and other breakfast foods, canned fruits and fruit sauces andthe like. Exemplary food and beverage products or formulations alsoinclude sweet coatings, frostings, or glazes for comestible products.

In yet another embodiment, the chemosensory receptor modifier andchemosensory receptor ligand modifier can be formulated, individually orin combination, in flavor preparations to be added to food and beverageformulations or products.

Typically at least a chemosensory receptor modulating amount, achemosensory receptor ligand modulating amount, a sweet flavormodulating amount, a sweet flavoring agent amount, or a sweet flavorenhancing amount of one or more of the chemosensory receptor modifiersor chemosensory receptor ligand modifiers of the present invention willbe added to the comestible or medicinal product, optionally in thepresence of known sweeteners, e.g., so that the sweet flavor modifiedcomestible or medicinal product has an increased sweet taste as comparedto the comestible or medicinal product prepared without the modifiers ofthe present invention, as judged by human beings or animals in general,or in the case of formulations testing, as judged by a majority of apanel of at least eight human taste testers, via procedures commonlyknown in the field.

The concentration of sweet flavoring agent needed to modulate or improvethe flavor of the comestible or medicinal product or composition will ofcourse depend on many variables, including the specific type ofcomestible composition and its various other ingredients, especially thepresence of other known sweet flavoring agents and the concentrationsthereof, the natural genetic variability and individual preferences andhealth conditions of various human beings tasting the compositions, andthe subjective effect of the particular compound on the taste of suchchemosensory compounds.

One application of the chemosensory receptor modifiers and/orchemosensory receptor ligand modifiers is for modulating (inducing,enhancing or inhibiting) the sweet taste or other taste properties ofother natural or synthetic sweet tastants, and comestible compositionsmade therefrom. A broad but also low range of concentrations of thecompounds or entities of the present invention would typically berequired, i.e., from about 0.001 ppm to 100 ppm, or narrower alternativeranges from about 0.1 ppm to about 10 ppm, from about 0.01 ppm to about30 ppm, from about 0.05 ppm to about 10 ppm, from about 0.01 ppm toabout 5 ppm, or from about 0.02 ppm to about 2 ppm, or from about 0.01ppm to about 1 ppm.

In yet another embodiment, the chemosensory receptor modifier andchemosensory receptor ligand modifier of the present invention can beprovided in pharmaceutical compositions containing a therapeuticallyeffective amount of one or more compounds of the present invention,preferably in purified form, together with a suitable amount of apharmaceutically acceptable vehicle, so as to provide the form forproper administration to a patient.

When administered to a patient, the compounds of the present inventionand pharmaceutically acceptable vehicles are preferably sterile. Wateris a preferred vehicle when a compound of the present invention isadministered intravenously. Saline solutions and aqueous dextrose andglycerol solutions can also be employed as liquid vehicles, particularlyfor injectable solutions. Suitable pharmaceutical vehicles also includeexcipients such as starch, glucose, lactose, sucrose, gelatin, malt,rice, flour, chalk, silica gel, sodium stearate, glycerol monostearate,talc, sodium chloride, dried skim milk, glycerol, propylene, glycol,water, ethanol and the like. The present pharmaceutical compositions, ifdesired, can also contain minor amounts of wetting or emulsifyingagents, or pH buffering agents. In addition, auxiliary, stabilizing,thickening, lubricating and coloring agents may be used.

Pharmaceutical compositions comprising a compound of the presentinvention may be manufactured by means of conventional mixing,dissolving, granulating, dragee-making, levigating, emulsifying,encapsulating, entrapping or lyophilizing processes. Pharmaceuticalcompositions may be formulated in conventional manner using one or morephysiologically acceptable carriers, diluents, excipients orauxiliaries, which facilitate processing of compounds of the presentinvention into preparations which can be used pharmaceutically. Properformulation is dependent upon the route of administration chosen.

The present pharmaceutical compositions can take the form of solutions,suspensions, emulsion, tablets, pills, pellets, capsules, capsulescontaining liquids, powders, sustained-release formulations,suppositories, emulsions, aerosols, sprays, suspensions, or any otherform suitable for use. In some embodiments, the pharmaceuticallyacceptable vehicle is a capsule (see e.g., Grosswald et al., U.S. Pat.No. 5,698,155). Other examples of suitable pharmaceutical vehicles havebeen described in the art (see Remington: The Science and Practice ofPharmacy, Philadelphia College of Pharmacy and Science, 20^(th) Edition,2000).

For topical administration a compound of the present invention may beformulated as solutions, gels, ointments, creams, suspensions, etc. asis well-known in the art.

Systemic formulations include those designed for administration byinjection, e.g., subcutaneous, intravenous, intramuscular, intrathecalor intraperitoneal injection, as well as those designed for transdermal,transmucosal, oral or pulmonary administration. Systemic formulationsmay be made in combination with a further active agent that improvesmucociliary clearance of airway mucus or reduces mucous viscosity. Theseactive agents include, but are not limited to, sodium channel blockers,antibiotics, N-acetyl cysteine, homocysteine and phospholipids.

In some embodiments, the compounds of the present invention areformulated in accordance with routine procedures as a pharmaceuticalcomposition adapted for intravenous administration to human beings.Typically, compounds of the present invention for intravenousadministration are solutions in sterile isotonic aqueous buffer. Forinjection, a compound of the present invention may be formulated inaqueous solutions, preferably in physiologically compatible buffers suchas Hanks' solution, Ringer's solution, or physiological saline buffer.The solution may contain formulatory agents such as suspending,stabilizing and/or dispersing agents. When necessary, the pharmaceuticalcompositions may also include a solubilizing agent.

Pharmaceutical compositions for intravenous administration mayoptionally include a local anesthetic such as lignocaine to ease pain atthe site of the injection. Generally, the ingredients are suppliedeither separately or mixed together in unit dosage form, for example, asa lyophilized powder or water free concentrate in a hermetically sealedcontainer such as an ampoule or sachette indicating the quantity ofactive agent. When the compound of the present invention is administeredby infusion, it can be dispensed, for example, with an infusion bottlecontaining sterile pharmaceutical grade water or saline. When thecompound of the present invention is administered by injection, anampoule of sterile water for injection or saline can be provided so thatthe ingredients may be mixed prior to administration.

For transmucosal administration, penetrants appropriate to the barrierto be permeated are used in the formulation. Such penetrants aregenerally known in the art.

Pharmaceutical compositions for oral delivery may be in the form oftablets, lozenges, aqueous or oily suspensions, granules, powders,emulsions, capsules, syrups, or elixirs, for example. Orallyadministered pharmaceutical compositions may contain one or moreoptionally agents, for example, sweetening agents such as fructose,aspartame or saccharin; flavoring agents such as peppermint, oil ofwintergreen, or cherry coloring agents and preserving agents, to providea pharmaceutically palatable preparation.

Moreover, where in tablet or pill form, the pharmaceutical compositionsmay be coated to delay disintegration and absorption in thegastrointestinal tract, thereby providing a sustained action over anextended period of time. Selectively permeable membranes surrounding anosmotically active driving compound are also suitable for orallyadministered compounds of the present invention. In these laterplatforms, fluid from the environment surrounding the capsule is imbibedby the driving compound, which swells to displace the agent or agentcomposition through an aperture. These delivery platforms can provide anessentially zero order delivery profile as opposed to the spikedprofiles of immediate release formulations. A time delay material suchas glycerol monostearate or glycerol stearate may also be used. Oralcompositions can include standard vehicles such as mannitol, lactose,starch, magnesium stearate, sodium saccharine, cellulose, magnesiumcarbonate, etc. Such vehicles are preferably of pharmaceutical grade.

For oral liquid preparations such as, for example, suspensions, elixirsand solutions, suitable carriers, excipients or diluents include water,saline, alkyleneglycols (e.g., propylene glycol), polyalkylene glycols(e.g., polyethylene glycol) oils, alcohols, slightly acidic buffersbetween pH 4 and pH 6 (e.g., acetate, citrate, ascorbate at betweenabout 5.0 mM to about 50.0 mM) etc. Additionally, flavoring agents,preservatives, coloring agents, bile salts, acylcarnitines and the likemay be added.

For buccal administration, the pharmaceutical compositions may take theform of tablets, lozenges, etc. formulated in conventional manner.

Liquid drug formulations suitable for use with nebulizers and liquidspray devices and EHD aerosol devices will typically include a compoundof the present invention with a pharmaceutically acceptable vehicle.Preferably, the pharmaceutically acceptable vehicle is a liquid such asalcohol, water, polyethylene glycol or a perfluorocarbon. Optionally,another material may be added to alter the aerosol properties of thesolution or suspension of compounds of the invention. Preferably, thismaterial is liquid such as an alcohol, glycol, polyglycol or a fattyacid. Other methods of formulating liquid drug solutions or suspensionsuitable for use in aerosol devices are known to those of skill in theart (see, e.g., Biesalski, U.S. Pat. No. 5,112,598; Biesalski, U.S. Pat.No. 5,556,611).

A compound of the present invention may also be formulated in rectal orvaginal pharmaceutical compositions such as suppositories or retentionenemas, e.g., containing conventional suppository bases such as cocoabutter or other glycerides.

In addition to the formulations described previously, a compound of thepresent invention may also be formulated as a depot preparation. Suchlong acting formulations may be administered by implantation (forexample, subcutaneously or intramuscularly) or by intramuscularinjection. Thus, for example, a compound of the present invention may beformulated with suitable polymeric or hydrophobic materials (forexample, as an emulsion in an acceptable oil) or ion exchange resins, oras sparingly soluble derivatives, for example, as a sparingly solublesalt.

When a compound of the present invention is acidic, it may be includedin any of the above-described formulations as the free acid, apharmaceutically acceptable salt, a solvate or hydrate. Pharmaceuticallyacceptable salts substantially retain the activity of the free acid, maybe prepared by reaction with bases and tend to be more soluble inaqueous and other protic solvents than the corresponding free acid form.

A compound of the present invention, and/or pharmaceutical compositionthereof, will generally be used in an amount effective to achieve theintended purpose. For use to treat or prevent diseases or disorders thecompounds of the present invention and/or pharmaceutical compositionsthereof, are administered or applied in a therapeutically effectiveamount.

The amount of a compound of the present invention that will be effectivein the treatment of a particular disorder or condition disclosed hereinwill depend on the nature of the disorder or condition and can bedetermined by standard clinical techniques known in the art. Inaddition, in vitro or in vivo assays may optionally be employed to helpidentify optimal dosage ranges. The amount of a compound of the presentinvention administered will, of course, be dependent on, among otherfactors, the subject being treated, the weight of the subject, theseverity of the affliction, the manner of administration and thejudgment of the prescribing physician.

For example, the dosage may be delivered in a pharmaceutical compositionby a single administration, by multiple applications or controlledrelease. In some embodiment, the compounds of the present invention aredelivered by oral sustained release administration. Dosing may berepeated intermittently, may be provided alone or in combination withother drugs and may continue as long as required for effective treatmentof the disease state or disorder.

Suitable dosage ranges for oral administration depend on potency, butare generally between about 0.001 mg to about 200 mg of a compound ofthe present invention per kilogram body weight. Dosage ranges may bereadily determined by methods known to the artisan of ordinary skill theart.

Suitable dosage ranges for intravenous (i.v.) administration are about0.01 mg to about 100 mg per kilogram body weight. Suitable dosage rangesfor intranasal administration are generally about 0.01 mg/kg body weightto about 1 mg/kg body weight. Suppositories generally contain about 0.01milligram to about 50 milligrams of a compound of the present inventionper kilogram body weight and comprise active ingredient in the range ofabout 0.5% to about 10% by weight. Recommended dosages for intradermal,intramuscular, intraperitoneal, subcutaneous, epidural, sublingual orintracerebral administration are in the range of about 0.001 mg to about200 mg per kilogram of body weight. Effective doses may be extrapolatedfrom dose-response curves derived from in vitro or animal model testsystems. Such animal models and systems are well-known in the art.

Preferably, a therapeutically effective dose of a compound of thepresent invention described herein will provide therapeutic benefitwithout causing substantial toxicity. Toxicity of compounds of thepresent invention may be determined using standard pharmaceuticalprocedures and may be readily ascertained by the skilled artisan. Thedose ratio between toxic and therapeutic effect is the therapeuticindex. A compound of the present invention will preferably exhibitparticularly high therapeutic indices in treating disease and disorders.The dosage of a compound of the present invention described herein willpreferably be within a range of circulating concentrations that includean effective dose with little or no toxicity.

In certain embodiments of the present invention, the compounds of thepresent invention and/or pharmaceutical compositions thereof can be usedin combination therapy with at least one other agent. The compound ofthe present invention and/or pharmaceutical composition thereof and theother agent can act additively or, more preferably, synergistically. Insome embodiments, a compound of the present invention and/orpharmaceutical composition thereof is administered concurrently with theadministration of another agent, which may be part of the samepharmaceutical composition as the compound of the present invention or adifferent pharmaceutical composition. In other embodiments, apharmaceutical composition of the present invention is administeredprior or subsequent to administration of another agent.

In still another embodiment, the chemosensory receptor modifiers andchemosensory receptor ligand modifiers of the present invention and/orpharmaceutical compositions thereof may be advantageously used in humanmedicine.

When used to treat and/or prevent diseases or disorders, the compoundsdescribed herein and/or pharmaceutical compositions may be administeredor applied singly, or in combination with other agents. The compoundsand/or pharmaceutical compositions thereof may also be administered orapplied singly, in combination with other active agents.

Methods of treatment and prophylaxis by administration to a patient of atherapeutically effective amount of a compound described herein and/orpharmaceutical composition thereof are provided herein. The patient maybe an animal, more preferably, a mammal and most preferably, a human.

In one example, the compounds described herein and/or pharmaceuticalcompositions thereof, are administered orally. The compounds of thepresent invention and/or pharmaceutical compositions thereof may also beadministered by any other convenient route, for example, by infusion orbolus injection, by absorption through epithelial or mucocutaneouslinings (e.g., oral mucosa, rectal and intestinal mucosa, etc.).Administration can be systemic or local. Various delivery systems areknown, (e.g., encapsulation in liposomes, microparticles, microcapsules,capsules, etc.) that can be used to administer a compound describedherein and/or pharmaceutical composition thereof. Methods ofadministration include, but are not limited to, intradermal,intramuscular, intraperitoneal, intravenous, subcutaneous, intranasal,epidural, oral, sublingual, intranasal, intracerebral, intravaginal,transdermal, rectally, by inhalation, or topically, particularly to theears, nose, eyes, or skin. The preferred mode of administration is leftto the discretion of the practitioner and will depend in-part upon thesite of the medical condition. In most instances, administration willresult in the release of the compounds and/or pharmaceuticalcompositions thereof into the bloodstream.

In another example, it may be desirable to administer one or morecompounds of the present invention and/or pharmaceutical compositionthereof locally to the area in need of treatment. This may be achieved,for example, and not by way of limitation, by local infusion duringsurgery, topical application, e.g., in conjunction with a wound dressingafter surgery, by injection, by means of a catheter, by means of asuppository, or by means of an implant, said implant being of a porous,non-porous, or gelatinous material, including membranes, such assialastic membranes, or fibers. In one embodiment, administration can beby direct injection at the site (or former site) of the condition.

In yet another example, it may be desirable to introduce one or morecompounds of the present invention and/or pharmaceutical compositionsthereof into the central nervous system by any suitable route, includingintraventricular, intrathecal and epidural injection. Intraventricularinjection may be facilitated by an intraventricular catheter, forexample, attached to a reservoir, such as an Ommaya reservoir.

A compound of the present invention and/or pharmaceutical compositionthereof may also be administered directly to the lung by inhalation. Foradministration by inhalation, a compound of the present invention and/orpharmaceutical composition thereof may be conveniently delivered to thelung by a number of different devices. For example, a Metered DoseInhaler (“MDI”), which utilizes canisters that contain a suitable lowboiling propellant, (e.g., dichlorodifluoromethane,trichlorofluoromethane, dichlorotetrafluoroethane, carbon dioxide or anyother suitable gas) may be used to deliver compounds of the presentinvention and/or pharmaceutical compositions thereof directly to thelung.

Alternatively, a Dry Powder Inhaler (“DPI”) device may be used toadminister a compound of the invention and/or pharmaceutical compositionthereof to the lung. DPI devices typically use a mechanism such as aburst of gas to create a cloud of dry powder inside a container, whichmay then be inhaled by the patient. DPI devices are also well known inthe art. A popular variation is the multiple dose DPI (“MDDPI”) system,which allows for the delivery of more than one therapeutic dose. Forexample, capsules and cartridges of gelatin for use in an inhaler orinsufflator may be formulated containing a powder mix of a compound ofthe present invention and a suitable powder base such as lactose orstarch for these systems.

Another type of device that may be used to deliver a compound of thepresent invention and/or pharmaceutical composition thereof to the lungis a liquid spray device supplied, for example, by Aradigm Corporation,Hayward, Calif. Liquid spray systems use extremely small nozzle holes toaerosolize liquid drug formulations that may then be directly inhaledinto the lung.

In yet another example, a nebulizer is used to deliver a compound of thepresent invention and/or pharmaceutical composition thereof to the lung.Nebulizers create aerosols from liquid drug formulations by using, forexample, ultrasonic energy to form fine particles that may be readilyinhaled (see e.g., Verschoyle et al., British J. Cancer, 1999, 80,Suppl. 2, 96). Examples of nebulizers include devices supplied bySheffield Pharmaceuticals, Inc (See, Armer et al., U.S. Pat. No.5,954,047; van der Linden et al., U.S. Pat. No. 5,950,619; van derLinden et al., U.S. Pat. No. 5,970,974), and Batelle PulmonaryTherapeutics, Columbus, Ohio.

In yet another example, an electrohydrodynamic (“EHD”) aerosol device isused to deliver a compound of the present invention and/orpharmaceutical composition thereof to the lung. EHD aerosol devices useelectrical energy to aerosolize liquid drug solutions or suspensions(see e.g., Noakes et al., U.S. Pat. No. 4,765,539). The electrochemicalproperties of the formulation may be important parameters to optimizewhen delivering a compound of the present invention and/orpharmaceutical composition thereof to the lung with an EHD aerosoldevice and such optimization is routinely performed by one of skill inthe art. EHD aerosol devices may more efficiently deliver compounds tothe lung than other pulmonary delivery technologies.

In yet another example, the compounds of the present invention and/orpharmaceutical compositions thereof can be delivered in a vesicle, inparticular a liposome (Langer, 1990, Science 249:1527-1533; Treat etal., in “Liposomes in the Therapy of Infectious Disease and Cancer,”Lopez-Berestein and Fidler (eds.), Liss, New York, pp. 353-365 (1989);see generally “Liposomes in the Therapy of Infectious Disease andCancer,” Lopez-Berestein and Fidler (eds.), Liss, New York, pp. 353-365(1989)).

In yet another example, the compounds of the present invention and/orpharmaceutical compositions thereof can be delivered via sustainedrelease systems, preferably oral sustained release systems. In oneembodiment, a pump may be used (See, Langer, supra, Sefton, 1987, CRCCrit. Ref Biomed Eng. 14:201; Saudek et al., 1989, N. Engl. J. Med.321:574).

In yet another example, polymeric materials can be used (see “MedicalApplications of Controlled Release,” Langer and Wise (eds.), CRC Pres.,Boca Raton, Fla. (1974); “Controlled Drug Bioavailability,” Drug ProductDesign and Performance, Smolen and Ball (eds.), Wiley, New York (1984);Langer et al., 1983, J Macromol. Sci. Rev. Macromol Chem. 23:61; seealso Levy et al., 1985, Science 228: 190; During et al., 1989, Ann.Neurol. 25:351; Howard et al., 1989, J. Neurosurg. 71:105).

In still other embodiments, polymeric materials are used for oralsustained release delivery. Preferred polymers include sodiumcarboxymethylcellulose, hydroxypropylcellulose,hydroxypropylmethylcellulose and hydroxyethylcellulose (most preferred,hydroxypropyl methylcellulose). Other preferred cellulose ethers havebeen described (Alderman, Int. J. Pharm. Tech. & Prod. Mfr., 1984, 5(3)1-9). Factors affecting drug release are well known to the skilledartisan and have been described in the art (Bamba et al., Int. J.Pharm., 1979, 2, 307).

In yet another example, enteric-coated preparations can be used for oralsustained release administration. Preferred coating materials includepolymers with a pH-dependent solubility (i.e., pH-controlled release),polymers with a slow or pH-dependent rate of swelling, dissolution orerosion (i.e., time-controlled release), polymers that are degraded byenzymes (i.e., enzyme-controlled release) and polymers that form firmlayers that are destroyed by an increase in pressure (i.e.,pressure-controlled release).

In still another example, osmotic delivery systems are used for oralsustained release administration (Verma et al., Drug Dev. Ind. Pharm.,2000, 26:695-708). In yet other embodiments, OROS™ osmotic devices areused for oral sustained release delivery devices (Theeuwes et al., U.S.Pat. No. 3,845,770; Theeuwes et al., U.S. Pat. No. 3,916,899).

In still another example, a controlled-release system can be placed inproximity of the target of the compounds and/or pharmaceuticalcomposition of the invention, thus requiring only a fraction of thesystemic dose (See, e.g., Goodson, in “Medical Applications ofControlled Release,” supra, vol. 2, pp. 115-138 (1984). Othercontrolled-release systems discussed in Langer, 1990, Science249:1527-1533 may also be used.

Having now generally described the invention, the same will be morereadily understood by reference to the following examples, which areprovided by way of illustration and are not intended as limiting. It isunderstood that various modifications and changes can be made to theherein disclosed exemplary embodiments without departing from the spiritand scope of the invention.

EXAMPLES Experiment 1 Modeling and Identification of PotentialChemosensory Receptor Ligand Enhancer

General Procedure

The general procedures for identifying a potential chemosensory receptorligand enhancer is summarized as the following.

1. Constructing a model of the structure of the Venus flytrap T1R2domain

2. Docking a chemosensory receptor ligand, e.g., a sweetener into theactive site of the structure of the Venus flytrap domain of T1R2, withor without T1R3 present

3. Docking a chemosensory receptor ligand enhancer, e.g., a sweetenhancer into the active site in the presence of the chemosensoryreceptor ligand, e.g., the sweetener

4. Selecting a chemosensory receptor ligand enhancer, e.g., sweetenhancer candidate based on two criteria: a) it fits the active site inthe model, and b) it forms productive interactions with the Venusflytrap domain of T1R2 and with the chemosensory receptor ligand, e.g.,the sweetener. Interactions can be van der Waals, burial of hydrophobicatoms or atomic groups, hydrogen bonds, ring stacking interactions, orsalt-bridging electrostatic interactions. Key residues for suchinteractions include the hinge residues, the near active site, thepincer residues, e.g., interacting residues described in the presentinvention. Candidates are not restricted to fitting completely withinthe active site, as it is open and chemosensory receptor ligand enhancercandidates may extend beyond the active site as long as they partiallyextend into it.

Model of the Structure

A model of the structure of the Venus Flytrap T1R2 domain may come fromcrystal structures of T1R2 or of T1R2 complexed with T1R3. The domainsmay be in open or in closed form, and may or may not be APO or contain aligand. Alternatively a model of the structure of the Venus Flytrap T1R2domain may be built using standard homology modeling methods usingcrystal structures of available Venus flytrap domains such as the mGluRreceptor Venus flytrap domains as templates to construct the model.

An example of a procedure for building such a model is to use thecommercial software Homology or Modeller from the Accelrys Corporationthat is well documented in the literature and available commercially.Alternative conformations of the model may further be explored usingadditional molecular mechanical techniques that may include but are notlimited to normal mode analysis to explore relative movement of thelobes of the model, loop generation techniques to generate alternativeconformations of loops in the model, or Monte Carlo and/or moleculardynamics simulations.

Docking

A chemosensory receptor ligand, e.g., sweetener was first docked intothe active site of T1R2. Its modeled pose in the active site wasselected by its ability to form productive van der Waals, ring stacking,hydrogen bonding, and/or salt bridging interactions with interactingresidues within the active site of the Venus flytrap domain of T1R2.

A candidate for a chemosensory receptor ligand modifier, e.g., sweetenhancer was then docked into the active site in the presence of theligand, e.g., the sweetener described in the previous paragraph. Itsactive pose and its candidacy as a potential chemosensory receptorligand modifier, e.g., sweet enhancer was based on its ability to formproductive interactions in the form of van der Waals, ring stacking,hydrogen bonding, and/or salt bridging interactions with interactingresidues described in the present invention, with additional residues ofthe T1R2 domain, and optionally with the chemosensory receptor ligand,e.g., the sweetener placed in the active site as described above.

Candidate for Chemosensory Receptor Ligand Modifiers

A molecule was considered a candidate if it can be docked into theactive site in the presence of a chemosensory receptor ligand, e.g.,sweetener, forming productive interactions with interacting residuesdescribed in the present invention. We defined two spaces within theactive site: a first space occupied by a chemosensory receptor ligand,e.g., sweetener, and a second space occupied by a chemosensory receptorligand modifier, e.g., enhancer. Modeling and mutagenesis resultsestablished key residues that were considered to be likely to line thesespaces for the chemosensory receptor ligand, e.g., sweeteners andchemosensory receptor ligand modifier, e.g., sweet enhancers. In thecontext of our study, “residue lining the space” meant that the residuehad backbone and/or side-chain atoms that were positioned so that theycan potentially interact with atoms of the chemosensory receptor ligand,e.g., sweetener (space #1) and/or chemosensory receptor ligand modifier,e.g., sweet enhancer (space #2). While the chemosensory receptor ligand,e.g., sweetener and chemosensory receptor ligand modifier, e.g., sweetenhancer themselves cannot occupy the same space, their correspondingspaces may overlap due to the ability of residues to contact both thechemosensory receptor ligand, e.g., sweetener and the chemosensoryreceptor ligand modifier, e.g., sweet enhancer, due to proteinflexibility, due to ligand flexibility, and due to the potential formultiple binding modes for a chemosensory receptor ligand, e.g.,sweetener or chemosensory receptor ligand modifier, e.g., sweetenhancer. Information on important residues lining space #1 and space #2came from modeling and docking and from site directed mutagenesis.

The hinge residues are considered to be associated with the first space(space #1). We have discovered that one of the spaces occupied by achemosensory receptor ligand, e.g., sweetener is partially lined byresidues herein called hinge residues. Many Venus flytrap domains havebeen crystallized with agonists including mGluR1, mGluR2, and mGluR3that show agonists forming interactions with homologous residues tothose identified herein for T1R2. Many chemosensory receptor ligands,e.g., sweeteners docked to the model of T1R2 can be docked to thisregion. Our site directed mutagenesis also provides strong evidence tosupport the finding that hinge residues or residues spatially adjacentto it are key residues to the activation of a chemosensory receptor,e.g., T1R2 related receptor. Since chemosensory receptor ligands, e.g.,sweeteners vary in size, there are additional residues lining this firstspace for larger residues where the list of these additional residues isdependent, partially on the size of the chemosensory receptor ligand,e.g., sweetener.

Pincer residues are considered to be associated with the second space(space #2). Venus flytrap domains are known to transition from an “open”state to a “closed” state on agonist binding. The flytrap domain iscomprised of two lobes commonly referred to in the literature as theupper lobe and lower lobe. In the “open” state the lobes are furtherapart, while in the closed state the lobes undergo a relative motionthat brings the upper and lower lobe closer together. In addition todirect stabilization of the closed state of T1R2 by the agonist, ourmodeling study has demonstrated that there is additional stabilizationof the closed state through interactions of residues on the upper lobewith corresponding residues on the lower lobe that are herein called the“pincer residues”. We have discovered that an interacting site, e.g.,interacting space for a chemosensory receptor ligand modifier, e.g.,sweet enhancer is the space that is partially lined by these pincerresidues, since additional interactions in this region can furtherstabilize the closed, agonized form of the Venus flytrap domain. Oursite directed mutagenesis study also provides evidence to support thefinding that pincer residues and residues spatially adjacent to them arekey residues associated with modulation of chemosensory receptor ligand,e.g., enhancement activity of the ligand.

The first space and second space can be swapped. In the above discussionthe chemosensory receptor modifier, e.g., sweetener binds to the hingewhile the chemosensory receptor ligand modifier, e.g., sweet enhancerbinds to the pincer region. This is just one example and should not beconstrued restrictively. For example, our modeling and docking study hasalso demonstrated that a likely binding mode for saccharine as anagonist (sweetener) involves binding to the pincer region. Such resultwas further supported by our site-directed mutagenesis. With achemosensory receptor modifier, e.g., sweetener bound to the pincerregion there is opportunity for further stabilization of the closed formof the Venus flytrap domain through binding of a chemosensory receptorligand modifier, e.g., sweet enhancer to the hinge region.

Procedural Definitions.

1. Docking

Docking is generally considered as the process of translating androtating the candidate molecule relative to a chemosensory receptor,e.g., T1R2 structural model while simultaneously adjusting internaltorsional angles of the candidate molecule to fit the candidate moleculeinto the active site of the chemosensory receptor, e.g., T1R2 structuralmodel. Poses of the candidate molecule (positions, relativeorientations, and internal torsions) are selected based on whether themolecule fits the active site, and whether the molecule can formproductive van der Waals interactions, hydrogen bonds, ring stackinginteractions, and salt bridge interactions with residues of the activesite and with the chemosensory receptor ligand, e.g., sweetener. Keyresidues can be identified. A candidate is considered more likely if itinteracts with sets of residues in the active site as the hinge region,the near active site, the pincer residues, and the totality of theactive site. It is also considered more likely if it forms directinteractions with a chemosensory receptor ligand, e.g., a sweetener.

2. Homology Modeling

Homology modeling is generally considered as the process of constructinga model of the Venus flytrap domain of a chemosensory receptor, e.g.,T1R2 from its amino acid sequence and from the three dimensionalcoordinates of one or more homologous Venus flytrap domain proteins.Homology modeling may be performed using standard methods well-describedin the literature and available in commercial software such as theHomology program or Modeler from the Accelrys Corporation. Models basedon experimentally determined structures of open and closed forms, aswell as animation of models using normal mode analysis, were used todefine the pincer residues discussed above.

Exemplary Illustrations of Modeling Studies

FIGS. 5 to 10 illustrate interacting spaces and residues associated withone of our molecular modeling studies.

Experiment 2 Mutagenesis Study for Identification of ChemosensoryReceptor Ligand Modifier Enhancer

In our previous patent applications (International Publication No.WO07047988 and International Publication No. WO070104709), we describeda method using human-rat chimeric sweet-umami chimeric receptors to mapthe binding sites of sweet and umami tastants. Our data demonstratedthat a number of sweeteners, including sucrose, fructose, aspartame,neotame, D-tryptophan (D-Trp), Acesulfame K, saccharin and dulcin, allinteract with the T1R2 Venus flytrap domain (VFT), while the umamitastants, including L-glutamate, inosine-5′-monophosphate (IMP), andguanosine-5′-monophosphate (GMP), all interact with the T1R1 Venusflytrap domain.

Under the guidance of molecular modeling, we performed site-directedmutagenesis on human T1R2 VFT. The mutagenesis was done using theroutine PCR-based method. Human T1R2 mutants were transientlytransfected into HEK293 cell together with the human T1R3 wild typecDNA, and the transfected cells were characterized using an automatedFLIPR machine or a calcium imaging system as described in our previouspatent applications. In order to control for plasma membrane expression,protein folding and other factors that might contribute to changes inreceptor activity, we used 2 sweeteners which interact with otherdomains of the human sweet receptor as positive controls. The 2 controlsweeteners were cyclamate and compound X (Senomyx). It is known from ourprevious data that cyclamate interacts with the human T1R3 transmembranedomain, while compound X interacts with the human T1R2 transmembranedomain.

The mutagenesis data for a number of sweeteners are summarized in thefollowing tables. Based on the data, we concluded that 6 residues (S40,S144, S165, Y103, D142, P277) are critical for interaction with thosesweeteners.

Mutagenesis Data on FLIPR

Aspartame D-Trp Fructose Sucrose Sucralose Cyclamate S3819 (15 Mm) (20mM) (200 mM) (200 mM) (3.2 mM) (80 mM) (25 μM) WT +++ +++ +++ +++ ++++++ +++ V384F ++ ++ ++ ++ ++ +++ +++ V384A ++ ++ ++ ++ ++ +++ +++E382A + ++ + + ++ ++ ++ S165I − − + + ++ ++ ++ D278A ++ ++ ++ + − ++++++ K65A ++ ++ + + + ++ ++ S165A +++ ++ ++ ++ ++ ++ +++ I67A +++ +++ ++++++ +++ +++ +++ N143A +++ ++ ++ ++ +++ +++ +++ S303A +++ +++ ++ ++ +++++ +++ Q328A +++ +++ +++ +++ +++ +++ +++ T184A +++ ++ +++ +++ +++ ++++++ T242A +++ ++ ++ ++ ++ +++ +++ L279A +++ +++ ++ ++ ++ ++ +++ T326A ++++ ++ ++ ++ ++ ++

Mutagenesis Data on Calcium Imaging

Aspartame D-Trp Fructose Sucrose Sucralose Cyclamate S3819 (15 mM) (20mM) (200 mM) (200 mM) (3.2 mM) (80 mM) (25 μM) WT ++ ++ ++ ++ ++ ++ ++I167A + + + + + + + Y103A − + + + − + + D278A + + + + − ++ ++ D307A + +− − + + + E302A − + + + + + + S165I − − + + + + + S40A − − − − − + +D142A − − − − − + + R383A − − − − − − + A305F − − − − − − + Y215A − − −− − − − D142I − − − − − − −

Additional Mutations on R383

Aspartame Neotame Sucrose Sucralose D-Trp Cyclamate S3819 (15 mM) (80μM) (200 mM) (3.2 mM) (20 mM) (80 mM) (25 μM) WT ++ +++ ++ +++ +++ ++++++ R383H + ++ + ++ ++ ++ ++ R383Q − + − + + + + R383I − − − − − − −R383F − ++ − − + + + R383K − + − + + + + R383N − + − + + + + R383S − +− + + + + R383A − − − − − − +

The sweet enhancer, compound A, is selective for the human sweetreceptor, and inactive on the rat sweet receptor. Using the previouslydescribed human-rat chimeric receptors, we mapped the binding site ofcompound A to hT1R2 VFT. As shown in FIG. 11, compound A enhanced thesucralose activity on human sweet receptor (h2/h3) but not rat sweetreceptor (r2/r3). When we replaced the rat receptor T1R2 VFT with itshuman counterpart (h2-r2/r3), the receptor can be enhanced by compoundA. On the other hand, when we replaced the human receptor T1R2 VFT withits rat counterpart (r2-h2/h3), the receptor can no longer be enhancedby compound A. We conclude that compound A interacts with human T1R2VFT. Due to the different sensitivity of human and rat receptors tosucralose, different sucralose concentrations were used to achieve ˜EC20of the different receptors.

Following compound A, 8 more analogues have been identified to enhancethe sucralose activity of human sweet receptor. The same mappingexperiments were carried out on these 8 analogues, and we observed thesame activity pattern as compound A as summarized in the followingtable. We conclude that all 8 compound A analogues interact with humanT1R2 VFT.

h2/h3 r2/r3 h2-r2/r3 r2-h2/h3 Compound A (25 μM) + − + − Compound A1 (25μM) + − + − Compound A2 (25 μM) + − + − Compound A3 (25 μM) + − + −Compound A4 (25 μM) + − + − Compound A5 (25 μM) + − + − Compound A6 (25μM) + − + − Compound A7 (25 μM) + − + − Compound A8 (100 μM) + − + −

After mapping the enhancers to human T1R2 VFT, we performed mutagenesisanalysis to further define the interaction site. As summarized in thefollowing table, six residues (K65, D278, L279, D307, R383, V384) wereidentified as critical for the activities of compound A and analogous.Interestingly, V384 is also important for the activities of 2structurally related sweeteners (as shown in FIG. 12), saccharin andacesulfame K (AceK), indicating that these sweeteners might occupysimilar space in the human T1R2 VFT. The concentrations for thesweeteners are Aspartame (15 mM), D-Trp (20 mM), Sucrose (200 mM),Sucralose (3.2 mM), AceK (8 mM), Saccharin (3.2 mM), Cyclamate (80 mM),S3819 (25 μM).

Enhancement Activity (at 25 μM) for Compound A and its analogs hT1R2Sucralose A A4 A1 A5 A2 A6 A3 A8 A7 WT ++ ++ ++ +++ ++ +++ ++ + ++ +++V384A ++ ++ ++ +++ ++ +++ ++ + ++ +++ E382A ++ ++ ++ +++ ++ +++ ++ + +++++ Y103A − + + ++ + ++ + + ++ ++ P277A + ++ + +++ + +++ + + ++ +++D278A* − ++ + +++ + +++ + + + ++ K65A + − − − − − − − − − L279A ++ − − −− − − − − − V384F ++ + + + + + + − − + S165I ++ ++ ++ +++ ++ +++ ++ + +++++ I67A ++ ++ ++ +++ ++ +++ ++ + ++ +++ S165A ++ + ++ +++ ++ +++ ++ +++ +++ N143A ++ ++ ++ +++ ++ +++ ++ + ++ +++ T326A ++ ++ ++ +++ ++ +++++ + ++ +++ T242A ++ ++ ++ +++ ++ +++ ++ + ++ +++ S303A ++ ++ ++ +++ +++++ ++ + ++ +++ Q328A ++ ++ ++ +++ ++ +++ ++ + ++ +++ T184V ++ ++ ++ +++++ +++ ++ + ++ +++ T184A ++ ++ ++ +++ ++ +++ ++ + ++ +++ V64M ++ ++ +++++ ++ +++ ++ + ++ +++ S168T ++ ++ ++ +++ ++ +++ ++ + ++ +++ R383H ++ ++++ +++ ++ +++ ++ + ++ +++ S40T + ++ ++ +++ ++ +++ ++ + ++ +++I167A + + + ++ + ++ + + + ++ E302A + + + ++ + ++ + + + ++ R383F + − − −− − − − − − D307A + − − − − − − − − − D142A − + + ++ + ++ + + + ++ S40A− + + ++ + ++ + + + ++ R383A − + + ++ + ++ + + + ++ A305F − − − − − − −− − − *D278 is a critical residue for the enhancers, because allenhancers in the above table show agonist activity on D278A mutant,i.e., they activate the mutant receptor in the absence of sucralose.

Experiment 3 Chemical Synthesis of the Compounds of the PresentInvention Example 14-Amino-5,6-dimethylthieno[2,3-d]pyrimidine-2(1H)-thione

A solution ofN-(3-cyano-4,5-dimethylthiophen-2-ylcarbamothioyl)benzamide (example 1a)(1.90 g, 6.03 mmol) and NaOH (2 N, 8.3 mL) in EtOH (25 mL) was stirredat 100° C. under nitrogen for half an hour. After cooling to roomtemperature, the clear reaction solution was filtered and the filtratewas carefully neutralized with 10% AcOH with vigorous stirring at 0° C.The resultant precipitate was collected by filtration, washed with warmwater and then 20% EtOH in water to give the final product4-amino-5,6-dimethylthieno[2,3-d]pyrimidine-2(1H)-thione (1.11 g, 87%)as an off-white solid. M.p.: >260° C. ¹H NMR (400 MHz, DMSO-d₆) δ2.25(s, 3H), 2.26 (s, 3H). MS 212 (MH⁺).

Example 1a N-(3-Cyano-4,5-dimethylthiophen-2-ylcarbamothioyl)benzamide

To a solution of 2-amino-4,5-dimethylthiophene-3-carbonitrile (1.52 g,10.0 mmol) in 1.4-dioxane (20 mL) was added benzoylisothiocyanate (1.63g, 10.0 mmol). The reaction mixture was then stirred at room temperatureunder nitrogen overnight. The precipitation was collected by filtration,washed with EtOAc/Hexanes (1:4), and dried under vacuum overnight togive N-(3-Cyano-4,5-dimethylthiophen-2-ylcarbamothioyl)benzamide as awhite solid. ¹H NMR (400 MHz, CDCl₃) δ2.23 (s, 3H), 2.31 (s, 3H),7.58-7.54 (m, 2H), 7.68-7.66 (m, 1H), 7.94 (d, J=7.2 Hz, 2H), 9.13 (bs,1H). MS 316 (MH⁺).

Example 2 4-Aminoquinazoline-2(1H)-thione

Prepared as in example 1 from N-(2-cyanophenylcarbamothioyl)benzamide(Example 2a). ¹H NMR (400 MHz, DMSO-d₆) δ7.25 (dt, J=1.0, 8.2 Hz, 1H),7.35 (d, J=8.2 Hz, 1H), 7.65 (dt, J=1.0, 8.2 Hz, 1H), 8.05 (dd, J=1.0,8.1 Hz, 1H), 8.30 (s, 1H), 8.35 (s, 1H), 12.34 (s, 1H). MS 178 (MH⁺).

Example 2a N-(2-Cyanophenylcarbamothioyl)benzamide

Prepared as in Example 1a from 2-aminobenzonitrile and benzoylisothiocyanate as a pale-yellow solid. ¹H NMR (400 MHz, DMSO-d₆)δ7.35-7.56 (m, 3H), 7.67 (t, 1H), 7.75-7.76 (d, J=5.2 Hz, 2H), 7.89-7.91(d, J=7.2 Hz, 2H), 7.98-8.01 (dd, J1=1.6 Hz, J2=8.2 Hz, 2H), 11.90 (s,1H), 12.54 (s, 1H). MS 282 (MH⁺).

Example 3 4-Amino-5-methylquinazoline-2(1H)-thione

Prepared as in example 1 fromN-(2-cyano-3-methylphenylcarbamothioyl)benzamide (Example 3a) as anoff-white solid. M.p.: >250° C. ¹H NMR (400 MHz, DMSO-d₆) δ2.68 (s, 3H),7.03 (d, J=6.8 Hz, 1H), 7.13 (b, 1H), 7.22 (d, J=6.8 Hz, 1H), 7.48 (t,J=6.8 Hz, 1H), 8.50 (b, 1H), 12.26 (s, 1H). ¹³C NMR (DMSO-d₆) δ23.26,109.86, 114.37, 127.16, 134.31, 136.97, 143.57, 160.58, 179.67. MS 192(MH⁺).

Example 3a N-(2-Cyanophenylcarbamothioyl)benzamide

Prepared as in example 1a from 2-amino-6-methylbenzonitrile and benzoylisothiocyanate as a pale-yellow solid. ¹H NMR (400 MHz, DMSO-d₆) δ7.40(m, 1H), 7.52-7.69 (m, 5H), 7.98-8.01 (m, 2H), 11.99 (s, 1H), 12.54 (s,1H). MS 296 (MH⁺).

Example 4 4-amino-5,6-dimethylthieno[2,3-d]pyrimidin-2(1H)-one

A solution of N-(3-cyano-4,5-dimethylthiophen-2-ylcarbamoyl)benzamide(example 4a) (44.35 g, 148.1 mmol) and NaOH (2 N, 204 mL) in EtOH (400mL) was stirred at 100° C. under nitrogen for four hours. The clearreaction solution was filtered and the filtrate was cooling to roomtemperature, and then was carefully neutralized with 10% AcOH (˜120 mL)with vigorous stirring at 0° C. After stirring overnight from 0° C. toroom temperature, the resultant precipitate was collected by filtration,washed with warm water (60-70° C., 150 mL×4) and 20% EtOH in water (200mL×2), and then dried at 50° C. under vacuum overnight to give the finalproduct 4-amino-5,6-dimethylthieno[2,3-d]pyrimidin-2(1H)-one (27.7 g,96%) as a white solid. ¹H NMR (400 MHz, DMSO-d₆) δ7.98 (brs, 1H), 2.24(s, 3H), 2.19 (s, 3H). MS 196 (MH⁺).

Example 4a N-(3-cyano-4,5-dimethylthiophen-2-ylcarbamoyl)benzamide

To a solution of 2-amino-4,5-dimethylthiophene-3-carbonitrile (example4b) (25 g, 164.5 mmol) in 1.4-dioxane (600 mL) was added benzoylisocyanate (24.2 g, 164.5 mmol). The reaction mixture was then stirredat room temperature under nitrogen overnight. The precipitate wascollected by filtration, washed with 1.4-dioxane (20 mL×3), and driedunder vacuum at 40° C. for 3 hours to giveN-(3-cyano-4,5-dimethylthiophen-2-ylcarbamoyl)benzamide (44.35 g, 90%)as a white solid. ¹H NMR (400 MHz, DMSO-d₆) δ2.10 (s, 3H), 2.24 (s, 3H),7.52-7.56 (m, 2H), 7.64-7.69 (m, 1H), 8.01-8.03 (m, 2H), 11.57 (brs,1H), 12.05 (brs, 1H). MS 300 (MH⁺).

Example 4b 2-amino-4,5-dimethylthiophene-3-carbonitrile

To a solution of butanone (162.0 mL, 1.8 mol), sulfur (57.99 g, 1.8mol), and malononitrile (119.49 g, 1.8 mol) in anhydrous Ethanol (1.2 L)was added at 0° C. triethylamine (251.4 mL, 1.8 mol). The reaction wasstirred at 0° C. for 15 minutes then heated at 80° C. for 70 minutes.After cooling to room temperature, ethanol (920 mL) was removed reducedpressure and aqueous NaCl (30%, 750 mL) was added. The resulting mixturewas stirred for 10 minutes and extracted with diethyl ether (1 L). Theaqueous layer was further extracted with diethyl ether (500 mL) and theinsoluble solids were removed by filtration after which the organiclayer was separated and combined with the first diethyl ether extract.The combined organic extract was dried over MgSO₄, filtered andconcentrated under reduced pressure. The residue was stirred for 2 hoursin dichloromethane (300 mL) and a solid was collected. More solid wasisolated from the dichloromethane solution cooled to −78° C. Thecombined solid product was refluxed in dichloromethane (600 mL) for 10minutes then stirred at room temperature for 30 minutes and cooled to−78° C. The resultant precipitate was collected by filtration to givethe crude product (115 g). The filtrate was concentrated and the residuewas chromatographed on silica gel (eluent: dichloromethane) to provide asolid that was combined with the previous crude product. The resultingresidue was purified by flash chromatography on silica gel(dichloromethane) to yield 2-amino-4,5-dimethylthiophene-3-carbonitrile(105 g, 38%) as an off white solid. ¹H NMR (400 MHz, DMSO-d₆) δ1.93 (d,J=1.2 Hz, 3H), 2.07 (d, J=1.2 Hz, 3H), 3.33 (s, 2H). MS 153 (MH⁺).

Example 5 4-Amino-5,6-butylenethieno[2,3-d]pyrimidine-2(1H)-thione

Prepared as in Example 1 from N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-ylcarbamothioyl)benzamide (Example 5a). ¹H NMR (400MHz, DMSO-d₆) δ1.75 (m, 4H), 2.62 (m, 2H), 2.74 (m, 2H). MS 238 (MH⁺).

Example 5aN-(3-Cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-ylcarbamothioyl)-benzamide

Prepared as in example 1a from2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile (example 5b)and benzoylisothiocyanate as a pale-yellow solid. MS 342 (MH⁺).

Example 5b 2-Amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile

A solution of cyclohexanone (1.96 g, 20.0 mmol), malononitrile (1.32 g,20.0 mmol), sulfur (640 mg, 20.0 mmol), and triethylamine (2.03 g, 20mmol) in EtOH (50 mL) was refluxed for 6 h under nitrogen. The solventwas removed under reduced pressure and the residue partitioned betweenEtOAc and water. The organic layer was separated, washed with brine, anddried over Na₂SO₄. After evaporation of the solvent, the residue waspurified by chromatography on silica gel eluting with EtOAc/Hexanes(2:3) to give the title product as a yellow solid. ¹H NMR (400 MHz,CDCl₃) δ1.79 (m, 4H), 2.50 (m, 4H), 4.59 (s, 2H). MS 179 (MH⁺).

Example 6 4-Amino-5-methylquinazolin-2(1H)-one

Prepared as in example 1 fromN-(2-cyano-3-methylphenylcarbamoyl)benzamide (example 6a). ¹H NMR (400MHz, DMSO-d₆) δ3.04 (s, 3H), 7.43 (d, J=7.2 Hz, 1H), 7.51 (d, J=7.2 Hz,1H), 7.97 (t, J=7.2 Hz, 1H). MS 176 (MH⁺).

Example 6a N-(2-Cyano-3-methylphenylcarbamoyl)benzamide

Prepared as in example 1a from 2-amino-6-methylbenzonitrile and benzoylisocyanate as an off-white solid. ¹H NMR (400 MHz, DMSO-d₆) δ7.19 (d,J=7.6 Hz, 1H), 7.52-7.68 (m, 5H), 8.02-8.08 (m, 2H), 11.32 (s, 1H),11.46 (s, 1H). MS 280 (MH⁺).

Example 7 4-Amino-6-ethyl-5-methylthieno[2,3-d]pyrimidin-2(1H)-one

Prepared as in Example 1 fromN-(3-cyano-5-ethyl-4-methylthiophen-2-ylcarbamoyl)benzamide (Example7a). ¹H NMR (400 MHz, DMSO-d₆) δ1.11 (t, J=7.6 Hz, 3H), 2.26 (s, 3H),2.60-2.67 (q, J=7.6 Hz, 2H). MS 210 (MH⁺).

Example 7a N-(3-Cyano-5-ethyl-4-methylthiophen-2-ylcarbamoyl)benzamide

Prepared as in example 1a from2-amino-5-ethyl-4-methylthiophene-3-carbonitrile (example 7b) andbenzoyl isocyanate as a pale-yellow solid. MS 314 (MH⁺).

Example 7b 2-Amino-5-ethyl-4-methylthiophene-3-carbonitrile

Prepared as in example 5b from 2-pentanone, malononitrile, and sulfur asa yellow solid. MS 167 (MH⁺).

Example 8 4-Amino-6-methylthieno[2,3-d]pyrimidin-2(1H)-one

Prepared as in Example 1 fromN-(3-cyano-5-methylthiophen-2-ylcarbamoyl)benzamide (Example 8a). ¹H NMR(400 MHz, DMSO-d₆) δ2.34 (s, 3H), 6.97 (s, 1H), 7.50 (s, 1H). MS 182(MH⁺).

Example 8a N-(3-Cyano-5-methylthiophen-2-ylcarbamoyl)benzamide

Prepared as in Example 1a from 2-amino-5-methylthiophene-3-carbonitrileand benzoyl isocyanate as a white solid. ¹H NMR (400 MHz, DMSO-d₆) δ2.36(d, J=1.2 Hz, 3H), 6.89 (d, J=1.2 Hz, 1H), 7.55 (t, J=8.0 Hz, 2H), 7.66(d, J=7.2 Hz, 1H), 8.03-8.01 (m, 2H), 11.60 (brs, 1H), 12.08 (bs, 1H).MS 286 (MH⁺).

Example 94-Amino-6-(hydroxymethyl)-5-methylthieno[2,3-d]pyrimidine-2(1H)-thione

Prepared as in Example 1 fromN-(3-cyano-5-(hydroxymethyl)-4-methylthiophen-2-ylcarbamothioyl)benzamide(Example 9a). ¹H NMR (400 MHz, DMSO-d₆) δ2.30 (s, 3H), 4.54-4.55 (d,J=5.2 Hz, 2H), 5.54 (t, 1H). MS 228 (MH⁺).

Example 9aN-(3-Cyano-5-(hydroxymethyl)-4-methylthiophen-2-ylcarbamothioyl)-benzamide

Prepared as in example 1a from2-amino-5-(hydroxymethyl)-4-methylthiophene-3-carbonitrile (Example 9b)and benzoyl isothiocyanate as a yellow solid. MS 332 (MH⁺).

Example 9b 2-Amino-5-(hydroxymethyl)-4-methylthiophene-3-carbonitrile

Prepared as in example 5b from 4-hydroxybutan-2-one, malononitrile, andsulfur as a yellow solid. ¹H NMR (400 MHz, DMSO-d₆) δ1.97 (s, 3H),4.30-4.31 (d, J=5.6 Hz, 2H), 5.10 (t, 1H), 7.00 (s, 2H).

Example 10 4-Amino-5,6,7,8-tetrahydroquinazoline-2(1H)-thione

Prepared as in Example 1 fromN-(2-cyanocyclohex-1-enylcarbamothioyl)benzamide (Example 10a) as awhite solid. ¹H NMR (400 MHz, DMSO-d₆) δ 1.60-1.65 (m, 4H), 2.13 (m,2H), 2.38 (m, 2H), 6.93 (s, 1H), 7.56 (s, 1H), 11.84 (s, 1H). MS 182(MH⁺).

Example 10a N-(2-Cyanocyclohex-1-enylcarbamothioyl)benzamide

Prepared as in Example 1a from 2-aminocyclohex-1-enecarbonitrile(Example 10b) and benzoyl isothiocyanate as a white solid. MS 286 (MH⁺).

Example 10b 2-Aminocyclohex-1-enecarbonitrile

A stirred mixture of 1,7-heptanedinitrile (24.44 g, 0.2 mol) and t-BuOK(22.44 g, 0.2 mol) was heated at 80° C. for 3 h under nitrogen. Themixture was then cooled down to room temperature and stored at thattemperature overnight. The residue was treated with water, and extractedwith ether (2×). The combined organic layers were washed with brine,dried over Na₂SO₄, filtered and concentrated. The residue was purifiedby recrystallization from MeOH to give the title compound as a whitesolid (18.2 g, 75%). ¹H NMR (400 MHz, CDCl₃) δ1.58-1.71 (m, 4H),2.12-2.20 (m, 4H), 4.23 (bs, 2H). MS 123 (MH⁺).

Example 11 4-Amino-6-methylthieno[2,3-d]pyrimidin-2(1H)-one

Prepared as in Example 1 from N-(3-cyanothiophen-2-ylcarbamoyl)benzamide(Example 11a). ¹H NMR (400 MHz, DMSO-d₆) δ6.97 (s, J=5.2 Hz, 1H), 7.31(d, J=6.0 Hz, 1H), 7.60 (s, 2H), 11.38 (bs, 1H). MS 168 (MH⁺).

Example 11a N-(3-Cyanothiophen-2-ylcarbamoyl)benzamide

Prepared as in Example 1a from 2-aminothiophene-3-carbonitrile andbenzoyl isocyanate as a white solid. ¹H NMR (400 MHz, DMSO-d₆)δ7.23-7.19 (m, 2H), 7.55 (t, J=8.0 Hz, 2H), 7.70-7.66 (m, 1H), 8.04-8.02(m, 2H), 11.62 (bs, 1H), 12.18 (bs, 1H). MS 272 (MH⁺).

Example 12 4-Aminoquinazolin-2(1H)-one

Prepared as in Example 1 from N-(2-cyanophenylcarbamoyl)benzamide(Example 12a) as a white solid (156 mg, 41%). ¹H NMR (400 MHz, DMSO-d₆)δ7.12-7.20 (m, 2H), 7.59-7.63 (m, 1H), 8.08-8.10 (d, 1H), 8.60 (b, 2H),11.2 (b, 1H). ¹³C NMR (DMSO-d₆) δ108.72, 115.98, 122.32, 125.51, 135.38,142.96, 154.96, 163.51. MS 162 (MH⁺).

Example 12a N-(2-Cyanophenylcarbamoyl)benzamide

Prepared as in Example 1a from 2-aminobenzonitrile and benzoylisocyanate as a white powder (661 mg, 59%). ¹H NMR (400 MHz, DMSO-d₆)δ7.27-7.29 (t, 1H), 7.52-7.56 (t, 1H), 7.64-7.74 (m, 2H), 7.82-7.85 (dd,1H), 8.02-8.04 (m, 2H), 8.22-8.24 (d, 1H). MS 266 (MH⁺).

Example 13 4-Amino-6-methoxy-5-methylthieno[2,3-d]pyrimidin-2(1H)-one

Prepared as in Example 1 fromN-(3-cyano-5-methoxy-4-methylthiophen-2-ylcarbamoyl)benzamide (Example13a). ¹H NMR (400 MHz, DMSO-d₆) δ2.19 (s, 3H), 3.78 (s, 3H), 2.74 (s,2H). MS 212 (MH⁺).

Example 13aN-(3-Cyano-5-methoxy-4-methylthiophen-2-ylcarbamoyl)benzamide

Prepared as in Example 1a from2-amino-5-methoxy-4-methylthiophene-3-carbonitrile (example 13b) andbenzoyl isocyanate as an off-white solid. ¹H NMR (400 MHz, DMSO-d₆)δ2.03 (s, 3H), 3.86 (s, 3H), 7.54 (t, J=7.2 Hz, 2H), 7.67 (t, J=7.6 Hz,1H), 8.01-8.03 (d, J=8.4 Hz, 2H), 11.60 (s, 1H), 12.03 (s, 1H). MS 316(MH⁺).

Example 13b 2-Amino-5-methoxy-4-methylthiophene-3-carbonitrile

Prepared as in Example 5b from 1-methoxypropan-2-one, malononitrile, andsulfur as a brown solid. MS 169 (MH⁺).

Example 14 4-Amino-6-methylquinazolin-2(1H)-one

Prepared as in Example 1 fromN-(2-cyano-4-methylphenylcarbamoyl)benzamide (Example 14a) as a whitesolid (259 mg, 57%). ¹H NMR (400 MHz, DMSO-d₆) δ2.29 (s, 3H), 6.99-7.05(m, 1H), 7.35-7.37 (d, 1H), 7.72 (b, 2H), 7.79 (s, 1H) 10.55 (bs, 1H).MS 176 (MH⁺).

Example 14a N-(2-Cyano-4-methylphenylcarbamoyl)benzamide

Prepared as in Example 1a from 2-amino-5-methylbenzonitrile (Example14b) as a white powder (724 mg, 46%). MS 280 (MH⁺).

Example 14b 2-Amino-5-methylbenzonitrile

5-Methyl-2-nitrobenzonitrile (1.92 g, 11.84 mmol) was added in portionsto a stirred solution of SnCl₂ (11.22 g, 59.2 mmol) in conc. HCl (12 mL)and EtOH (12 mL). The reaction temperature was maintained at 20-30° C.using an ice bath. The reaction mixture was then stirred at roomtemperature for 1 h and poured into an ice cold aqueous solution of NaOH(6N, app. 30 mL) to neutralize to pH7. The product was extracted intoEtOAc, washed with brine, dried over MgSO₄ and concentrated to providethe title product (1.56 g, 99%) as a yellow-brown solid. ¹H NMR (400MHz, DMSO-d₆) δ2.21 (s, 3H), 5.79 (bs, 2H), 6.68-6.71 (d, 1H), 7.10-7.13(dd, 1H), 7.15 (s, 1H). ¹³C NMR (DMSO-d₆) δ20.13, 93.99, 116.12, 118.94,125.38, 132.32, 135.76, 150.21. MS 133 (MH⁺).

Example 15 4-Amino-8-methylquinazolin-2(1H)-one

Prepared as in Example 1 fromN-(2-cyano-6-methylphenylcarbamoyl)benzamide (Example 15a) as a whitesolid (60 mg, 56%). ¹H NMR (400 MHz, DMSO-d₆) δ2.29 (s, 3H), 6.96-7.00(t, 1H), 7.37-7.38 (d, 1H), 7.70-7.72 (b, 2H), 7.80-7.82 (d, 1H), 9.87(bs, 1H). MS 176 (MH⁺).

Example 15a N-(2-Cyano-6-methylphenylcarbamoyl)benzamide

Prepared as in Example 1a from 2-amino-3-methylbenzonitrile (Example15b) and benzoyl isocyanate as a white powder (186 mg, 67%). MS 280(MH⁺).

Example 15b 2-Amino-3-methylbenzonitrile

To a solution of 2-bromo-6-methylaniline (126 μL, 1 mmol) in dry NMP (3mL) was added CuCN (197 mg, 2.2 mmol). The mixture was irradiated in amicrowave at 220° C. for 40 minutes, cooled to room temperature andpoured into a mixture of ammonia (50% w/v, 10 mL) and ice. The mixturewas stirred for 30 min and the product was extracted withdichloromethane (3×20 mL). The organic layers were combined, washed withwater and brine, dried over MgSO₄ and concentrated. The crude materialwas purified on silica gel (50% EtOAc/hexanes) to yield a brown oil thatcrystallized on standing (128 mg, 96%). ¹H NMR (400 MHz, DMSO-d₆) δ2.08(s, 3H), 5.68 (bs, 2H), 6.51-6.55 (t, 1H), 7.17-7.19 (d, 1H), 7.22-7.24(dd, 1H). MS 133 (MH⁺).

Example 16 4-Aminopyrimido[4,5-d]pyrimidin-2(1H)-one

Prepared as in Example 1 fromN-(2-cyano-4,5-dimethylfuran-3-ylcarbamoyl)benzamide (Example 16a). ¹HNMR (400 MHz, DMSO-d₆) δ8.91 (s, 1H), 8.92 (s, 1H), 9.24 (s, 2H), 11.50(b, 1H). MS 164 (MH⁺).

Example 16a N-(2-Cyano-4,5-dimethylfuran-3-ylcarbamoyl)benzamide

Prepared as in Example 1a from 4-aminopyrimidine-5-carbonitrile andbenzoyl isocyanate as an off-white powder. MS 268 (MH⁺).

Example 17 4-Amino-7-methylquinazoline-2(1H)-thione

Prepared as in Example 1 fromN-(2-cyano-5-methylphenylcarbamothioyl)benzamide (Example 17a). ¹H NMR(400 MHz, DMSO-d₆) δ2.35 (s, 3H), 7.08 (d, J=8.0 Hz, 1H), 7.13 (s, 1H),7.93 (d, J=8.0 Hz, 1H), 8.21 (s, 1H), 8.24 (s, 1H), 12.26 (s, 1H). MS192 (MH⁺).

Example 17a N-(2-Cyano-5-methylphenylcarbamothioyl)benzamide

Prepared as in Example 1a from 2-amino-4-methylbenzonitrile and benzoylisothiocyanate as a pale-yellow powder. ¹H NMR (400 MHz, DMSO-d₆) δ7.32(d, J=8.0 Hz, 1H), 7.51-7.58 (m, 3H), 7.67 (t, J=7.8 Hz, 1H), 7.78 (d,J=8.0 Hz, 1H), 7.98-8.01 (m, 2H), 11.88 (s, 1H), 12.49 (s, 1H). MS 296(MH⁺).

Example 18 4-Amino-5,6-dimethylfuro[2,3-d]pyrimidin-2(1H)-one

Prepared as in Example 1 fromN-(2-cyano-4,5-dimethylfuran-3-ylcarbamoyl)benzamide (Example 18a). ¹HNMR (400 MHz, DMSO-d₆) δ2.11 (s, 3H), 2.20 (s, 3H). MS 180 (MH⁺).

Example 18a N-(2-Cyano-4,5-dimethylfuran-3-ylcarbamoyl)benzamide

Prepared in a similar manner to Example 1a from2-amino-4,5-dimethylfuran-3-carbonitrile and benzoyl isocyanate as anoff-white solid. MS 284 (MH⁺).

Example 19 4-Amino-7-methylquinazolin-2(1H)-one

Prepared as in Example 1 fromN-(2-cyano-5-methylphenylcarbamoyl)benzamide (Example 19a). ¹H NMR (400MHz, DMSO-d₆) δ2.59 (s, 3H), 7.37 (s, 1H), 7.49 (d, J=7.2 Hz, 1H), 8.21(d, J=7.2 Hz, 1H). MS 176 (MH⁺).

Example 19a N-(2-Cyano-5-methylphenylcarbamoyl)benzamide

Prepared as in Example 1a from 2-amino-4-methylbenzonitrile and benzoylisocyanate as a white solid. ¹H NMR (400 MHz, DMSO-d₆) δ7.10-7.13 (m,1H), 7.54 (t, J=7.8 Hz, 2H), 7.66 (t, J=7.8 Hz, 1H), 7.71 (d, J=8.0 Hz,1H), 8.02-8.04 (m, 2H), 8.07 (s, 1H), 11.32 (s, 1H), 11.44 (s, 1H). MS280 (MH⁺).

Example 204-Amino-1-benzyl-5,6-dimethylthieno[2,3-d]pyrimidine-2(1H)-thione

Prepared as in Example 1 fromN-(benzyl(3-cyano-4,5-dimethylthiophen-2-yl)carbamothioyl)benzamide(Example 20a). MS 302 (MH⁺).

Example 20aN-(Benzyl(3-cyano-4,5-dimethylthiophen-2-yl)carbamothioyl)-benzamide

Prepared as in Example 1a from2-(benzylamino)-4,5-dimethylthiophene-3-carbonitrile (Example 20b) andbenzoyl isothiocyanate. MS 406 (MH⁺).

Example 20b 2-(Benzylamino)-4,5-dimethylthiophene-3-carbonitrile

To a solution of 2-amino-4,5-dimethylthiophene-3-carbonitrile (151 mg,1.0 mmol) and benzaldehyde (106 mg, 1 mmol) in 15 mL of 4% acetic acidin dichloroethane was added silica supported cyanoborohydride (2.0 g.2.0 mmol). The reaction was placed in a microwave reactor for 5 minutesat 135° C. Silica supported cyanoborohydride was removed by filtration,and the product was purified by prep HPLC using acetonitrile/water assolvent. MS 243 (MH⁺).

Example 21 4-Amino-1-ethyl-5,6-dimethylthieno[2,3-d]pyrimidin-2(1H)-one

Prepared as in Example 1 fromN-((3-cyano-4,5-dimethylthiophen-2-yl)(ethyl)carbamoyl)benzamide(Example 21a). MS 224 (MH⁺).

Example 21aN-((3-Cyano-4,5-dimethylthiophen-2-yl)(ethyl)carbamoyl)benzamide

Prepared in a similar manner to Example 1a from2-(ethylamino)-4,5-dimethylthiophene-3-carbonitrile (Example 21b) andbenzoyl isocyanate. MS 328 (MH⁺).

Example 21b 2-(Ethylamino)-4,5-dimethylthiophene-3-carbonitrile

To a mixture of 2-(benzylamino)-4,5-dimethylthiophene-3-carbonitrile(302 mg, 2.0 mmol), potassium carbonate (276 mg, 2.0 mmol), and acatalytic amount of potassium iodide in acetonitrile (1 mL) in a 20 mLmicrowave vial was added ethyl iodide (310 mg, 2.0 mmol). The reactionvial was placed in a microwave reactor for 15 minutes at 165° C. Thereaction mixture was dissolved in ethyl acetate and washed with waterand brine. The ethyl acetate portion was dried over sodium sulfate andsolvent was evaporated under reduced pressure, and the product waspurified by prep HPLC using acetonitrile/water as solvent. MS 181 (MH⁺).

Example 22 4-Amino-1,5,6-trimethylthieno[2,3-d]pyrimidin-2(1H)-one

Prepared as in Example 1 fromN-((3-cyano-4,5-dimethylthiophen-2-yl)(methyl)carbamoyl)benzamide(Example 22a). MS 210 (MH⁺).

Example 22aN-((3-Cyano-4,5-dimethylthiophen-2-yl)(methyl)carbamoyl)-benzamide

Prepared as in Example 1a from4,5-dimethyl-2-(methylamino)thiophene-3-carbonitrile (Example 22b) andbenzoyl isocyanate. MS 314 (MH⁺).

Example 22b 4,5-Dimethyl-2-(methylamino)thiophene-3-carbonitrile

Prepared as in Example 21b from2-amino-4,5-dimethylthiophene-3-carbonitrile and methyl iodide.

Example 23 1H-Benzo[c][1,2,6]thiadiazin-4-amine-2,2-dioxide

A stirred mixture of 2-cyanoaniline (236 mg, 2.0 mmol), sulfamide (192mg, 2.0 mmol) and DBU (304 mg, 2.0 mmol) was heated at 160° C. undernitrogen for 3 days. After cooling to room temperature, the reactionmixture was diluted with water and extracted three times with EtOAc. Theaqueous layer was removed under vacuum and the residue was purified bychromatography on silica gel eluting with 10% MeOH in dichloromethane togive the title compound as a pale yellow solid. ¹H NMR (400 MHz,DMSO-d₆) δ7.03 (dd, J=0.8, 8.0 Hz, 1H), 7.12 (dt, J=0.8, 8.0 Hz, 1H),7.56 (dt, J=0.8, 8.0 Hz, 1H), 7.85 (dd, J=0.8, 8.0 Hz, 1H). MS 198(MH⁺).

Example 24 5-Methyl-1H-benzo[c][1,2,6]thiadiazin-4-amine-2,2-dioxide

A solution of N-(2-cyano-3-methylphenyl)sulfamide (Example 24a) (211 mg,1.0 mmol) in EtOH was treated with NaOH (2.0 N, 1.0 mL, 2.0 mmol) andthe resultant solution was heated to 100° C. and stirred at thattemperature for 0.5 h. After cooling to room temperature, the clearreaction solution was filtered and the filtration was carefullyneutralized with 10% AcOH while with vigorous stirring at 0° C. Theresultant precipitate was collected by filtration, washed with warmwater and 20% EtOH in water to give the title product5-Methyl-1H-benzo[c][1,2,6]thiadiazin-4-amine-2,2-dioxide as anoff-white solid. ¹H NMR (400 MHz, DMSO-d₆) δ2.59 (s, 3H), 6.85-6.87 (d,J=8.4 Hz, 1H), 6.92-6.94 (d, J=7.2 Hz, 1H), 7.24 (s, 1H), 7.37 (t, J=7.6Hz, 1H), 8.24 (s, 1H), 10.76 (s, 1H). MS 212 (MH⁺).

Example 24a N-(2-Cyano-3-methylphenyl)sulfamide

A solution of 2-amino-6-methylbenzonitrile (1.32 g, 10 mmol) andsulfamide (4.81 g, 50 mmol) in dry 1,4-dioxane (50 mL) was refluxedunder nitrogen for 3 days. After the reaction mixture was cooled down toroom temperature, the precipitate was filtered and washed with dioxane.The filtrate was concentrated under reduced pressure, and the residuewas purified by chromatography on silica gel eluting with EtOAc/hexanes(3:7) to give the title compound as a pale-white solid. ¹H NMR (400 MHz,DMSO-d₆) δ2.44 (s, 3H), 7.19-7.21 (m, 3H), 7.39-7.41 (d, J=8.4 Hz, 1H),7.53 (t, J=8.0 Hz, 1H), 9.41 (s, 1H).

Example 25 5,6-Dimethyl-2-(methylthio)thieno[2,3-d]pyrimidin-4-amine

To a suspension ofN-(3-cyano-4,5-dimethylthiophen-2-ylcarbamothioyl)-benzamide (Example1a) (1.33 g, 4.22 mmol) in ethanol (25 mL) was added NaOH (2.0 N, 5.8mL) at room temperature under nitrogen. After stirring at 100° C. undernitrogen for 0.5 h, the reaction mixture was cooled in an ice bath andMeI (0.8 mL) was added dropwise. After stirring for another 0.5 h, theresulting precipitate was collected by filtration, rinsed with water,20% EtOH/H₂O, and dried under vacuum to give the title compound (840 mg,89%). ¹H NMR (400 MHz, DMSO-d₆) δ2.32 (s, 3H), 2.34 (s, 3H), 2.42 (s,3H), 6.93 (bs, 2H). MS 226 (MH⁺).

Example 26 2-Methoxy-5,6-dimethylthieno[2,3-d]pyrimidin-4-amine

Prepared in a similar manner to Example 25 fromN-(3-cyano-4,5-dimethylthiophen-2-ylcarbamoyl)benzamide (Example 4a) andmethyl iodide in 86% yield. ¹H NMR (400 MHz, CDCl₃) δ2.35 (s, 3H), 2.36(s, 3H), 3.53 (s, 3H), 6.0 (bs, 2H). MS 210 (MH⁺).

Example 27 5,6-Dimethyl-2-(methylthio)furo[2,3-d]pyrimidin-4-amine

Prepared as in Example 25 fromN-(2-cyano-4,5-dimethylfuran-3-ylcarbamothioyl)benzamide (Example 27a).¹H NMR (400 MHz, DMSO-d₆) δ2.16 (s, 3H), 2.23 (s, 3H), 2.41 (s, 3H),6.92 (s, 2H). MS 210 (MH⁺).

Example 27a N-(2-Cyano-4,5-dimethylfuran-3-ylcarbamothioyl)benzamide

Prepared as in Example 1a from 2-amino-4,5-dimethylfuran-3-carbonitrileand benzoyl isothiocyanate. MS 300 (MH⁺).

Example 28 7-Methyl-2-(methylthio)quinazolin-4-amine

Prepared as in Example 25 fromN-(2-cyano-5-methylphenylcarbamothioyl)benzamide (Example 17a). ¹H NMR(400 MHz, DMSO-d₆) δ2.40 (s, 3H), 2.45 (s, 3H), 7.17 (dd, J=2.0, 8.8 Hz,1H), 7.32 (s, 1H), 7.71 (b, 2H), 8.01 (d, J=8.4 Hz, 1H). MS 206 (MH⁺).

Example 29 5-Methyl-2-(methylthio)quinazolin-4-amine

Prepared as in Example 25 fromN-(2-cyano-3-methylphenylcarbamothioyl)benzamide (Example 3a). ¹H NMR(400 MHz, DMSO-d₆) δ2.46 (s, 3H), 2.75 (s, 3H), 7.11 (d, J=7.2 Hz, 1H),7.33 (d, J=7.2 Hz, 1H), 7.51 (dd, J=0.8, 7.2 Hz, 1H). MS 206 (MH⁺).

Example 30 5,6-Dimethylthieno[2,3-d]pyrimidine-2,4-diamine

A mixture of 2-amino-4,5-dimethylthiophene-3-carbonitrile (500 mg, 3.29mmol), cyanoguanidine (276.6 mg, 3.29 mmol) and HCl (2 N, 1.5 mL) inwater (10 mL) was refluxed under nitrogen for 2 h. The reaction mixturewas cooled to room temperature, and basified with diluted NaOH aqueoussolution to PH 7˜8. After evaporation of water, the residue was purifiedby preparative HPLC eluting with acetonitrile and water to give thetitle compound (33 mg, 5%). ¹H NMR (400 MHz, DMSO-d₆) δ2.22 (s, 3H),2.27 (s, 3H), 5.85 (bs, 2H), 6.29 (bs, 2H). MS 195 (MH⁺).

Example 31 2,5,6-Trimethylthieno[2,3-d]pyrimidin-4-amine

A mixture of 2-amino-4,5-dimethylthiophene-3-carbonitrile (200 mg, 1.32mmol), ammonia acetate (204 mg, 2.64 mmol), and triethyl orthoacetate(2.0 mL) was stirred in a sealed tube at 120° C. overnight. After thereaction mixture was cooling down to room temperature, the precipitatewas collected by filtration, rinsed with EtOAc and dried in the air togive title compound (52 mg, 60%) as a yellow solid. ¹H NMR (400 MHz,CDCl₃) δ2.41 (s, 3H), 2.45 (s, 3H), 2.56 (s, 3H), 5.28 (bs, 2H). MS 194(MH⁺).

Example 32 5,6-Dimethylthieno[2,3-d]pyrimidin-4-amine

Prepared as in Example 31 from2-amino-4,5-dimethylthiophene-3-carbonitrile and triethyl orthoformate.¹H NMR (400 MHz, DMSO-d₆) δ2.36 (s, 3H), 2.39 (s, 3H), 6.85 (bs, 2H),8.14 (s, 1H). MS 180 (MH⁺).

Example 33 2-Ethyl-5,6-dimethylthieno[2,3-d]pyrimidin-4-amine

Prepared as in Example 31 from2-amino-4,5-dimethylthiophene-3-carbonitrile and triethylorthopropanate. ¹H NMR (400 MHz, DMSO-d₆) δ1.19 (t, J=7.6 Hz, 3H), 2.33(s, 3H), 2.36 (s, 3H), 2.61 (q, J=7.6 Hz, 2H), 6.74 (bs, 2H). MS 208(MH⁺).

Example 34 5,6-Dimethyl-2-phenylthieno[2,3-d]pyrimidin-4-amine

A mixture of 2-amino-4,5-dimethylthiophene-3-carbonitrile (152 mg, 1.0mmol), ammonia acetate (308.3 mg, 4.0 mmol) and triethyl orthobenzoate(2.0 mL) in a sealed tube was put in a microwave at 200° C. for 20 min.After the reaction mixture was cooled to room temperature, it wasdiluted with EtOAc, washed with saturated NaHCO₃ and H₂O. The solventwas removed by vacuum and the residue was purified by preparative HPLCeluting with acetonitrile and water to give the title compound (80 mg,31%). ¹H NMR (400 MHz, CDCl₃) δ2.45 (s, 3H), 2.48 (s, 3H), 5.34 (bs,2H), 7.46-7.43 (m, 3H), 8.4-8.38 (m, 2H). MS 256 (MH⁺).

Example 35 5,6-Dimethyl-2-propylthieno[2,3-d]pyrimidin-4-amine

Prepared as in Example 34 from2-amino-4,5-dimethylthiophene-3-carbonitrile and triethyl orthobutanate.¹H NMR (400 MHz, DMSO-d₆) δ0.87 (t, J=7.6 Hz, 3H), 1.72-1.67 (m, 2H),2.33 (s, 3H), 2.36 (s, 3H), 2.57 (t, J=7.2 Hz, 2H), 6.73 (bs, 2H). MS222 (MH⁺).

Example 36 5,6-Dimethyl-2-(methylsulfonyl)thieno[2,3-d]pyrimidin-4-amine

To a suspension of5,6-dimethyl-2-(methylthio)thieno[2,3-d]pyrimidin-4-amine (Example 1)(200 mg, 0.89 mmol) in DCM (25 mL) was added m-chloroperoxybenzoic acid(767 mg, 4.44 mmol). After stirring at room temperature overnight, thereaction mixture was diluted with EtOAc, washed with water and brine,dried over Na₂SO₄, filtered and evaporated. The residue was purified bypreparative HPLC eluting with acetonitrile and water to give the titlecompound (45 mg, 20%). ¹H NMR (400 MHz, DMSO-d₆) δ2.42 (s, 6H), 3.27 (s,3H). MS 258 (MH⁺).

Example 37 Ethyl5,6-dimethyl-2-thioxo-1,2-dihydrothieno[2,3-d]pyrimidin-4-ylcarbamate

To a suspension of4-amino-5,6-dimethylthieno[2,3-d]pyrimidine-2(1H)-thione (211 mg, 1mmol) in DMF (5 mL) was added Et₃N (0.21 mL, 1.5 mmol) and ethylchloroformate (0.143 mL, 1.5 mmol). The reaction mixture was stirred atroom temperature overnight, then diluted with EtOAc, washed with waterand brine, dried over Na₂SO₄, filtered and evaporated. The residue waspurified on Biotage SP-1 eluting with EtOAc/hexane to give the titlecompound (154 mg, 54%). ¹H NMR (400 MHz, DMSO-d₆) δ1.22 (t, J=7.2 Hz,3H), 2.38 (s, 3H), 2.39 (s, 3H), 4.25 (q, J=7.2 Hz, 2H), 7.25-7.21 (m,2H). MS 284 (MH⁺)

Example 38 2-Chloroquinazolin-4-amine

To a solution of 2,4-dichloroquinazoline (2.0 g, 10 mmol) in THF (10mL), was added ammonia (28-30% in water, 18 mL). The reaction mixturewas stirred at room temperature overnight. The reaction mixture wasdiluted with EtOAc, washed with saturated NaHCO₃, water and brine, driedover Na₂SO₄, filtered and evaporated. The resulting solid was washedwith EtOAc to give the title compound (1.3 g, 72%). ¹H NMR (400 MHz,DMSO-d₆) δ7.52-7.48 (m, 1H), 7.6-7.58 (m, 1H), 7.8-7.76 (m, 1H),8.22-8.20 (m, 1H), 8.32 (bs, 2H).

Example 39 2-Chloro-N-methylquinazolin-4-amine

Prepared as in Example 38 from 2,4-dichloroquinazoline and methylamine.¹H NMR (400 MHz, DMSO-d₆) δ2.98 (d, J=4.4 Hz, 3H), 7.53-7.49 (m, 1H),7.61-7.58 (m, 1H), 7.79-7.75 (m, 1H), 88.19-8.17 (m, 1H), 78 (bs, 1H).

Example 40 2-Chloro-N,N-dimethylquinazolin-4-amine

Prepared as in Example 38 from 2,4-dichloroquinazoline anddimethylamine. ¹H NMR (400 MHz, CDCl₃) δ3.42 (s, 6H), 7.42-7.39 (m, 1H),7.72-7.70 (m, 1H), 7.79-7.77 (m, 1H), 8.03-8.01 (m, 1H). MS 208 (MH⁺).

Example 41 N2,N2,N4,N4-Tetramethylquinazoline-2,4-diamine

Prepared as in Example 38 from 2,4-dichloroquinazoline anddimethylamine. ¹H NMR (400 MHz, CDCl₃) δ3.27-3.23 (m, 12H), 7.01-6.97(m, 1H), 7.51-7.47 (m, 2H), 7.80-7.78 (m, 1H). MS 217 (MH⁺).

Example 42 2-Hydrazinylquinazolin-4-amine

A mixture of 2-chloroquinazolin-4-amine (Example 38) (100 mg, 0.56 mmol)and hydrazine (0.09 mL, 2.79 mmol) in ethanol (5 mL) was heated in asealed tube at 80° C. overnight. After the reaction mixture was cooleddown, the resulting precipitate was collected by filtration, rinsed withethanol and dried in the air to give the title compound (84 mg, 86%). ¹HNMR (400 MHz, DMSO-d₆) δ4.2 (bs, 2H), 4.6 (bs, 2H), 7.0 (t, J=7.2 Hz,1H), 7.27 (d, J=8.0 Hz, 1H), 7.43 (s, 1H), 7.61 (s, 1H), 7.87 (d, J=7.6Hz, 1H).

Example 43 2-(Hydroxyamino)quinazolin-4-amine

Prepared as in Example 42 from 2-chloroquinazolin-4-amine (Example 38)and hydroxylamine. ¹H NMR (400 MHz, DMSO-d₆) δ7.44-7.35 (m, 2H),7.78-7.74 (m, 2H), 8.24-8.22 (m, 1H), 8.95-8.76 (m, 2H). MS 177 (MH⁺).

Example 44 2-(Methoxyamino)quinazolin-4-amine

Prepared as in Example 42 from 2-chloroquinazolin-4-amine (Example 38)and methoxylamine. ¹H NMR (400 MHz, DMSO-d₆) δ3.79 (s, 3H), 7.48-7.44(m, 1H), 7.86-7.80 (m, 2H), 8.27 (d, J=8.0 Hz, 1H), 8.99 (s, 1H), 9.16(s, 1H), 12.39-12.08 (m, 1H). MS 191 (MH⁺).

Example 45 N′-(4-Aminoquinazolin-2-yl)acetohydrazide

Prepared as in Example 42 from 2-chloroquinazolin-4-amine (Example 38)and methoxylamine. ¹H NMR (400 MHz, DMSO-d₆) δ1.86 (s, 3H), 7.09 (t,J=7.2 Hz, 1H), 7.27 (d, J=8.4 Hz, 1H), 7.54-7.44 (m, 3H), 8.04-7.99 (m,2H), 9.63 (s, 1H). MS 218 (MH⁺).

Example 46 4-(Methylamino)quinazoline-2(1H)-thione

A mixture of 2-chloro-N-methylquinazolin-4-amine (Example 39) (100 mg,0.52 mmol), thiourea (47.5 mg, 0.62 mmol) and formic acid (0.02 mL, 0.52mmol) in ethanol (5 mL) was refluxed for 1.5 h. After cooling to roomtemperature, the reaction mixture was neutralized with diluted NaOHaqueous solution. The solvent was removed under vacuum and the residuewas purified by preparative HPLC eluting with acetonitrile and water togive the title compound (18 mg, 18%). ¹H NMR (400 MHz, DMSO-d₆) δ2.99(d, J=4.8 Hz, 3H), 7.25 (t, J=7.6 Hz, 1H), 7.35 (d, J=8.0 Hz, 1H),7.65-7.61 (m, 1H), 8.0 (d, J=8.0 Hz, 1H), 8.70 (d, J=4.4 Hz, 1H), 12.32(s, 1H). MS 192 (MH⁺).

Example 47 4-(Dimethylamino)quinazoline-2(1H)-thione

Prepared as in Example 46 from 2-chloro-N,N-dimethylquinazolin-4-amine(Example 40) and thiourea. ¹H NMR (400 MHz, DMSO-d₆) δ3.31 (s, 6H),7.24-7.19 (m, 1H), 7.40-7.38 (m, 1H), 7.65-7.61 (m, 1H), 8.00 (d, J=8.0Hz, 1H), 12.35 (s, 1H). MS 206 (MH⁺).

Example 48 5,6,7,8-Tetrahydroquinazoline-2,4(1H,3H)-dione

A solution of 2-oxocyclohexanecarbonitrile (615 mg, 5.0 mmol) and urea(600 mg, 10.0 mmol) in 1.25 N HCl in EtOH (20 mL) was refluxed overnight. After it was cooled down to 0° C., the precipitation wascollected by filtration, washed with EtOH/H₂O, and dried under vacuumovernight to give the product as a white solid. ¹H NMR (400 MHz, CD₃OD)δ1.67-1.80 (m, 4H), 2.25-2.29 (m, 2H), 2.38-2.42 (m, 2H). MS 167 (MH⁺).

Example 49 5,7-Dihydrothieno[3,4-d]pyrimidine-2,4(1H,3H)-dione

Prepared as in Example 48 from 4-oxotetrahydrothiophene-3-carbonitrileas a white solid. ¹H NMR (400 MHz, DMSO-d₆) δ3.74 (t, J=3.6 Hz, 2H),3.96 (t, J=3.6 Hz, 2H), 11.06 (s, 1H), 11.21 (s, 1H). MS 171 (MH⁺).

Example 505,6-Dimethyl-2-thioxo-2,3-dihydrothieno[2,3-d]pyrimidin-4(1H)-one

To a suspension of ethyl4,5-dimethyl-2-thioureidothiophene-3-carboxylate (Example 50a) (37 mg,0.17 mmol) in dry EtOH (10 mL) was added sodium hydroxide (21 mg, 0.52mmol). The reaction mixture was then stirred at room temperature for 5minutes and refluxed for 10 minutes. The reaction mixture was cooled toroom temperature, neutralized with 10% AcOH and then concentrated todryness. The residue was purified by chromatography on silica gel(Gradient 0-50% EtOAc in Hexanes) to give the title compound (8 mg) in24% yield. ¹H NMR (400 MHz, DMSO-d₆) δ2.25 (s, 6H), 12.24 (s, 1H), 13.27(s, 1H). MS 202 (MH⁺).

Example 50a Ethyl 4,5-dimethyl-2-thioureidothiophene-3-carboxylate

To a solution of ethyl2-isothiocyanato-4,5-dimethylthiophene-3-carboxylate (Example 50b) (1.21g, 5.27 mmol) in dichloromethane (10 mL) was added ammonia (7 M in MeOH,1.12 mL, 7.91 mmol) at 0° C. The reaction mixture was then stirred atroom temperature for 3 h, quenched with water and extracted withdichloromethane (3×). The combined organic layers were washed withbrine, dried over MgSO₄, filtered and concentrated. The dark orangeresidue was purified by chromatography on silica gel (Gradient 0-50%EtOAc in Hexanes) to give the title compound (37.1 mg, 3%). ¹H NMR (400MHz, DMSO-d₆) δ1.32 (t, 3H, J=7.1 Hz), 2.18 (s, 3H), 2.19 (s, 3H), 4.30(q, 2H, J=7.1 Hz), 8.43 (s, 2H), 11.38 (s, 1H). MS 259 (MH⁺).

Example 50b Ethyl 2-isothiocyanato-4,5-dimethylthiophene-3-carboxylate

To a mixture of thiophosgene (5.10 mL, 7.64 mmol) and calcium carbonate(1.05 g, 10.54 mmol) in CHCl₃/H₂O (½ by volume, 6 mL) was added dropwisea solution of ethyl 2-amino-4,5-dimethylthiophene-3-carboxylate (1.05 g,5.27 mmol) in CHCl₃ (7 mL) at 0° C. over a period of 1 h. The reactionmixture was the stirred for 2.5 h at 0° C., washed with water (3×). Theorganic layer was dried over MgSO₄, filtered and concentrated to givethe title compound (1.21 g, 100%). ¹H NMR (400 MHz, DMSO-d₆) δ1.32 (t,3H, J=7.1 Hz), 2.19 (s, 3H), 2.30 (s, 3H), 4.28 (q, 2H, J=7.1 Hz).

Example 51 4-Ethyl-5,6-dimethylthieno[2,3-d]pyrimidin-2(1H)-one

To a solution of 1-(4,5-dimethyl-3-propionylthiophen-2-yl)urea (Example51a) (15.4 mg, 0.068 mmol) in dry EtOH (10 mL) was added sodiumhydroxide (8.4 mg, 0.20 mmol). The reaction mixture was then stirred atRT for 30 minutes under nitrogen. The reaction mixture was neutralizedwith 10% AcOH and then concentrated to dryness. The residue was purifiedby chromatography on silica gel (Gradient 0-10% MeOH in dichloromethane)to give the title compound (2.7 mg, 19%). ¹H NMR (400 MHz, CDCl₃) δ1.42(t, J=7.6 Hz, 3H), 2.31 (s, 3H), 2.33 (s, 3H), 3.06 (q, J=7.6 Hz, 2H).MS 209 (MH⁺).

Example 51a 1-(4,5-Dimethyl-3-propionylthiophen-2-yl)urea

To a solution of triphosgene (68 mg, 0.224 mmol) in dry dichloromethane(2 mL) was added dropwise a mixture of1-(2-amino-4,5-dimethylthiophen-3-yl)propan-1-one (Example 51b) (111 mg,0.605 mmol) and DIEA (0.24 mL, 1.344 mmol) in dry dichloromethane (3.5mL) over a period of 20 minutes. After the reaction mixture was stirredfor 5 minutes, a mixture of ammonia (7 M in MeOH, 0.086 mL, 0.605 mmol)and DIEA (0.24 mL, 1.344 mmol) in dry dichloromethane (2 mL) was addedin one portion. The reaction mixture was then stirred at roomtemperature for 1 h under nitrogen. The reaction mixture wasconcentrated to dryness. The residue was dissolved in EtOAc (50 mL) andthen washed with 10% NaHSO₄, 5% NaHCO₃, and brine. The organic layer wasdried over MgSO₄, filtered and concentrated. The yellow residue waspurified by chromatography on silica gel (Gradient 0-50% EtOAc inHexanes) to give the title compound (15.4 mg, 30%). ¹H NMR (400 MHz,CDCl₃) δ1.18 (t, 3H, J=7.2 Hz), 2.25 (s, 3H), 2.30 (s, 3H), 2.87 (q, 2H,J=7.2 Hz), 4.77 (s, 2H), 11.99 (s, 1H). MS 227 (MH⁺).

Example 51b 1-(2-Amino-4,5-dimethylthiophen-3-yl)propan-1-one

To a solution of 3-oxopentanenitrile (971 mg, 10 mmol) in dry EtOH (100mL) was added sulfur (2.57 g, 10 mmol), butanone (0.91 mL, 10 mmol) andmorpholine (0.88 mL, 10 mmol) at room temperature under nitrogen. Thereaction mixture was then refluxed at 90° C. for 6 h, and then stirredovernight at room temperature under nitrogen. The orange brown reactionmixture was concentrated. The residue was diluted with water, andextracted with EtOAc (2×). The combined organic layers were washed withbrine, dried over MgSO₄, filtered and concentrated. The residue waspurified twice: first by chromatography on silica gel (Gradient 0-25%EtOAc in hexanes), and then by Prep HPLC (0-90% acetonitrile in water)to give the title compound (123 mg, 7%). ¹H NMR (400 MHz, CDCl₃) δ1.17(t, 3H, J=7.2 Hz), 2.17 (s, 3H), 2.24 (s, 3H), 2.78 (q, 2H, J=7.2 Hz),6.81 (s, 2H). MS 184 (MH⁺).

Example 52 4-Ethyl-5,6-dimethylthieno[2,3-d]pyrimidin-2(1H)-one

To a solution of methylmagnesium bromide (3.0 M in ether, 4.0 mL, 12.0mmol) in dry ether (5 mL) was added dropwise a solution of2-aminobenzonitrile (723 mg, 6.0 mmol) in dry ether (5 mL) at RT undernitrogen. After it was refluxed for 2 h under nitrogen, the reactionmixture was cooled down to 0° C. and methyl chloroformate (0.7 mL, 9.0mmol) was added dropwise. Dry THF (5 mL) was added to dissolve theresultant precipitate. The reaction mixture was then refluxed overnightunder nitrogen. The reaction mixture was acidified with 1N HCl and thenneutralized with 5% NaHCO₃ aqueous solution. The water mixture waswashed with EtOAc and the water layer was concentrated. The residue waspurified by Prep HPLC ((0-90% acetonitrile in water) to give the titlecompound (15.2 mg). ¹H NMR (400 MHz, CD₃OD) δ2.79 (s, 3H), 7.33 (d,J=7.1 Hz, 1H), 7.34 (t, J=7.1 Hz, 1H), 7.75 (td, J=1.2, 7.8 Hz, 1H),8.03 (dd, J=1.2 8.4 Hz, 1H). MS 161 (MH⁺).

Example 53 4-aminopyrido[2,3-d]pyrimidin-2(1H)-one

A solution of N-(3-cyanopyridin-2-ylcarbamoyl)benzamide (example 53a)(360 mg, 1.35 mmol) and NaOH (2 N, 1.85 mL) in EtOH (5 mL) was stirredat 100° C. under nitrogen for half an hour. After cooling to roomtemperature, the clear reaction solution was filtered and the filtratewas carefully neutralized with 10% AcOH with vigorous stirring at 0° C.The resultant precipitate was collected by filtration, and washed withwarm 20% EtOH in water to give the final product4-aminopyrido[2,3-d]pyrimidin-2(1H)-one (120 mg, 55%) as a white solid.¹H NMR (400 MHz, DMSO-d₆) δ7.22 (dd, J=4.4 Hz, 4.8 Hz, 1H), 7.29 (dd,J=4.8 Hz, 1H), 8.24 (dd, J=2 Hz, 1.6 Hz, 1H), 8.59 (dd, J=2 Hz, 1.6 Hz,1H), 8.66-8.71 (m, 2H), 8.70 (d, J=1.2 Hz, 1H). MS 162 (MH⁺).

Example 53a N-(3-cyanopyridin-2-ylcarbamoyl)benzamide

To a solution of 2-amino-3-cyanopyridine (300 mg, 2.5 mmol) in1.4-dioxane (5 mL) was added benzoyl isocyanate (370 mg, 2.5 mmol). Thereaction mixture was then stirred at room temperature under nitrogenovernight. The precipitation was collected by filtration, washed withEtOAc/Hexanes (1:4), and dried under vacuum to giveN-(3-cyanopyridin-2-ylcarbamoyl)benzamide as a white solid (360 mg,54%). MS 266 (MH⁺).

Example 54 5,6-dimethylquinazoline-2,4(1H,3H)-dione

Prepared as in Example 53 fromN-(2-cyano-3,4-dimethylphenylcarbamoyl)benzamide (Example 54a) as awhite solid (90 mg, 66%). ¹H NMR (400 MHz, DMSO-d₆) δ2.24 (s, 3H), 2.54(s, 3H), 6.87 (d, J=8.4 Hz, 1H), 7.32 (d, J=8.4 Hz, 1H), 10.51 (s, 1H).MS 189 (MH⁺).

Example 54a N-(2-cyano-3,4-dimethylphenylcarbamoyl)benzamide

Prepared as in Example 53a from 6-amino-2,3-dimethylbenzonitrile andbenzoyl isocyanate as a off-white solid (210 mg, 72%). ¹H NMR (400 MHz,DMSO-d₆) δ2.27 (s, 3H), 2.43 (s, 3H), 7.48 (d, J=6.4 Hz, 2H), 7.53 (t,J=8 Hz, 7.6 Hz, 2H), 7.65 (t, J=7.2 Hz, 1H), 7.94 (d, J=8 Hz, 1H), 8.03(d, J=7.6 Hz, 2H), 11.29 (s, 1H), 11.37 (s, 1H). MS 293 (MH⁺).

Example 55 4-amino-7-methoxyquinazolin-2(1H)-one

Prepared as in example 53 fromN-(2-cyano-5-methoxyphenylcarbamoyl)benzamide (Example 55a) as a whitesolid (24 mg, 37%). ¹H NMR (400 MHz, DMSO-d₆) δ3.79 (s, 3H), 6.63 (d,J=4 Hz, 1H), 6.67 (dd, J=2.4 Hz, 2.8 Hz, 1H), 7.67 (br, 2H), 7.89 (d,J=8.8 Hz, 1H), 10.61 (s, 1H). MS 191 (MH⁺).

Example 55a N-(2-cyano-5-methoxyphenylcarbamoyl)benzamide

Prepared as in Example 53a from 2-amino-4-methoxybenzonitrile andbenzoyl isocyanate as white solid (99 mg, 45%). ¹H NMR (400 MHz,DMSO-d₆) δ3.86 (s, 3H), 6.87 (dd, J=2.5 Hz, 2.4 Hz, 1H), 7.54 (t, J=8Hz, 2H), 7.66 (t, J=1.2 Hz, 1H), 7.77 (d, J=7.2 Hz, 1H), 7.89 (d, J=8.4Hz, 1H), 8.03 (d, J=2.8 Hz, 2H), 11.35 (s, 1H), 11.52 (s, 1H). MS 295(MH⁺).

Example 56 4-amino-5-methoxyquinazolin-2(1H)-one

Prepared as in example 53 fromN-(2-cyano-3-methoxyphenylcarbamoyl)benzamide (Example 56a) as a lightyellow solid (35 mg, 51%). ¹H NMR (400 MHz, DMSO-d₆) δ3.93 (s, 3H), 6.67(dd, J=7.6 Hz, 8.4 Hz, 2H), 7.45 (t, J=8 Hz, 1H), 7.75 (s, 1H),7.93-7.97 (br, 1H), 10.69 (s, 1H). MS 191 (MH⁺).

Example 56a N-(2-cyano-3-methoxyphenylcarbamoyl)benzamide

Prepared as in Example 53a from 2-amino-6-methoxybenzonitrile andbenzoyl isocyanate as light orange solid (118 mg, 41%). ¹H NMR (400 MHz,DMSO-d₆) δ3.94 (s, 3H), 6.98 (d, J=8 Hz, 1H), 7.54 (t, J=8 hz, 2H), 7.64(t, J=8.4 Hz, 2H), 7.88 (d, J=8.4 Hz, 1H), 8.04 (d, J=5.6 Hz, 2H), 11.35(s, 1H), 11.51 (s, 1H). MS 295 (MH⁺).

Example 57 4-amino-5-hydroxyquinazolin-2(1H)-one

Prepared as in example 53 fromN-(2-cyano-3-hydroxyphenylcarbamoyl)benzamide (Example 57a) as a greensolid (50 mg, 53%). ¹H NMR (400 MHz, DMSO-d₆) δ6.66 (d, J=8.4 Hz, 1H),6.73 (d, J=7.6 Hz, 1H), 7.57 (t, J=8.8 Hz, 1H), 9.47 (s, 1H), 9.68 (s,1H), 11.84 (s, 1H). MS 177 (MH⁺).

Example 57a N-(2-cyano-3-hydroxyphenylcarbamoyl)benzamide

Prepared as in Example 53a from 2-amino-6-hydroxybenzonitrile andbenzoyl isocyanate as an off-white solid (166 mg, 46%). ¹H NMR (400 MHz,DMSO-d₆) δ6.76 (d, J=8.4 Hz, 1H), 7.46 (t, J=8 Hz, 1H), 7.54 (t, J=8 Hz,2H), 7.66-7.73 (m, 2H), 8.04-8.06 (d, J=8 Hz, 2H), 11.24 (s, 1H), 11.30(s, 1H), 11.42 (s, 1H). MS 281 (MH⁺).

Example 58 4-amino-7-hydroxyquinazolin-2(1H)-one

Prepared as in example 53 fromN-(2-cyano-5-hydroxyphenylcarbamoyl)benzamide (Example 58a) as a lightgrey solid (104 mg, 41%). ¹H NMR (400 MHz, DMSO-d₆) δ6.51 (s, 2H), 6.52(d, J=2.4 Hz, 1H), 7.69-7.72 (br, 1H), 7.82 (d, J=9.2 Hz, 2H), 10.57(br, 1H). MS 177 (MH⁺).

Example 58a N-(2-cyano-5-hydroxyphenylcarbamoyl)benzamide

Prepared as in Example 53a, but refluxed in acetone instead of1,4-dioxane, from 2-amino-4-hydroxybenzonitrile and benzoyl isocyanateas a yellow solid (399 mg, 94%). MS 281 (MH⁺).

Example 59 4-amino-8-methoxyquinazolin-2(1H)-one

Prepared as in example 53 fromN-(2-cyano-6-methoxyphenylcarbamoyl)benzamide (Example 59a) as a darkwhite solid (75 mg, 39%). ¹H NMR (400 MHz, DMSO-d₆) δ3.86 (s, 3H), 7.02(t, J=8.4 Hz, 1H), 7.17 (d, J=7.2 Hz, 1H), 7.56 (d, J=7.6 Hz, 1H), 7.85(br, 2H), 9.73 (s, 1H). MS 191 (MH⁺).

Example 59a N-(2-cyano-6-methoxyphenylcarbamoyl)benzamide

Prepared as in Example 53a from 2-amino-3-methoxybenzonitrile andbenzoyl isocyanate as a light orange solid (280 mg, 95%). ¹H NMR (400MHz, DMSO-d₆) δ3.89 (s, 3H), 7.42 (t, J=3.2 Hz, 2H), 7.46 (d, J=3.6 Hz,1H), 7.54 (t, J=8 Hz, 2H), 7.66 (t, J=7.6 Hz, 1H), 8.05 (d, J=8.6 Hz,2H), 10.55 (s, 1H), 11.32 (s, 1H). MS 295 (MH⁺).

Example 60 8-amino-[1,3]dioxolo[4,5-g]quinazolin-6(5H)-one

Prepared as in example 53 fromN-(6-cyanobenzo[d][1,3]dioxol-5-ylcarbamoyl)benzamide (Example 60a) as alight yellow solid (80 mg, 77%). ¹H NMR (400 MHz, DMSO-d₆) δ6.24 (s,2H), 6.74 (s, 1H), 7.75 (s, 1H), 9.36 (d, J=10.4 Hz, 1H), 9.80 (d, J=7.2Hz, 1H), 12.01 (s, 1H). MS 205 (MH⁺).

Example 60a N-(6-cyanobenzo[d][1,3]dioxol-5-ylcarbamoyl)benzamide

Prepared as in Example 53a from6-aminobenzo[d][1,3]dioxole-5-carbonitrile and benzoyl isocyanate as ayellow solid (157 mg, 82%). ¹H NMR (400 MHz, DMSO-d₆) δ6.19 (s, 2H),7.42 (s, 1H), 7.54 (t, J=8 Hz, 2H), 7.66 (t, J=7.6 Hz, 1H), 7.74 (s,1H), 8.03 (d, J=9.2 Hz, 2H), 11.32 (d, J=12.8 Hz, 2H). MS 309 (MH⁺).

Example 61 4-(Methoxyamino)quinazolin-2(1H)-one

To a suspension of 2,4-dichloroquinazoline (995 mg, 5.0 mmol) in dryEtOH (100 mL), were added methoxyamine hydrochloride (569 mg, 5.5 mmol)and NaOH (227 mg, 5.5 mmol) in one portion at 0° C. The reaction mixturewas stirred at 0° C. for 1 hour, then placed in a refrigerator at 4° C.for 72 h. Upon completion, the reaction was concentrated, and theresidue was dissolved in EtOAc and washed with saturated NaHCO₃ (1×) andbrine (1×). The organic phase was dried over MgSO₄, filtered andconcentrated. The crude product was purified by preparative HPLC (10-90%CH₃CN in H₂O) to provide 4-(methoxyamino)quinazolin-2(1H)-one (556 mg,36%) as an off-white solid. ¹H NMR (400 MHz, DMSO-d₆) δ3.68 (s, 3H),7.02 (t, J=7.4 Hz, 1H), 7.35 (d, J=7.9 Hz, 1H), 7.52 (ddd, J=8.1, 7.0,1.5 Hz, 1H), 7.77 (dd, J=7.8, 1.4 Hz, 1H), 10.13 (br s, 1H), 10.89 (brs, 1H). MS 192.2 (MH⁺).

Example 62 4-Ethoxyquinazolin-2(1H)-one

Purification by preparative HPLC (10-90% CH₃CN in H₂O) of the crudereaction of example 61 also provided 4-ethoxyquinazolin-2(1H)-one (90mg, 9%) as an off-white solid. ¹H NMR (400 MHz, DMSO-d₆) δ1.35 (t, J=7.0Hz, 3H), 4.44 (q, J=7.0 Hz, 2H), 7.34 (ddd, J=8.1, 7.0, 1.2 Hz, 1H),7.46 (dd, J=8.2, 1.0 Hz, 1H), 7.71 (ddd, J=8.5, 7.0, 1.2 Hz, 1H), 8.01(dd, J=8.2, 1.5 Hz, 1H), 12.25 (br s, 1H). MS 191.1 (MH⁺).

Example 634-Amino-5-methyl-2-oxo-1,2-dihydrothieno[2,3-d]pyrimidine-6-carboxylicacid

To a solution of tert-butyl4-amino-5-methyl-2-oxo-1,2-dihydrothieno[2,3-d]pyrimidine-6-carboxylate(example 64a) (10.7 g, 38.03 mmol) in CH₂Cl₂ (25 mL), was addedtrifluoroacetic acid (25 mL, 324.5 mmol). The reaction mixture wasstirred at rt overnight. The precipitated solid was collected byfiltration, and washed with CH₂Cl₂ to yield4-Amino-5-methyl-2-oxo-1,2-dihydrothieno[2,3-d]pyrimidine-6-carboxylicacid (6.98 g, 82%) as a light brown solid. ¹H NMR (400 MHz, DMSO-d₆)δ2.78 (s, 3H). MS 226.0 (MH⁺).

Example 64 tert-Butyl4-amino-5-methyl-2-oxo-1,2-dihydrothieno[2,3-d]pyrimidine-6-carboxylate

To a suspension of tert-butyl5-(3-benzoylureido)-4-cyano-3-methylthiophene-2-carboxylate (example64a) (18 g, 60.52 mmol) in EtOH (200 mL) was added NaOH (75 mL, 2N). Thesuspension became clear, and the mixture was heated to reflux for 30min. After cooling to rt, the reaction was filtered, and the filtratewas cooled to 0° C. in an ice/water bath. The solution was neutralizedwith 10% acetic acid. The precipitated solid was collected byfiltration, and heated in EtOH at 80° C. under N₂ for 20 min. Aftercooling to rt, the product was collected by filtration and washed with10% EtOH in H₂O to yield tert-Butyl4-amino-5-methyl-2-oxo-1,2-dihydrothieno[2,3-d]pyrimidine-6-carboxylate(10.73 g, 63%) as a brown solid. ¹H NMR (400 MHz, DMSO-d₆) δ1.51 (s,9H), 2.73 (s, 3H), 3.18 (s, 2H). MS 282.2 (MH⁺).

Example 64a tert-butyl5-(3-benzoylureido)-4-cyano-3-methylthiophene-2-carboxylate

To a solution of tert-butyl5-amino-4-cyano-3-methylthiophene-2-carboxylate (example 64b) (16 g,67.14 mmol) in dioxane (200 mL), was added benzoyl isocyanate (10 g,67.14 mmol). The reaction mixture was stirred at rt overnight, and uponcompletion was diluted with EtOAc, washed with NaHCO₃, water, brine,dried over MgSO₄, filtered and concentrated to yield tert-butyl5-(3-benzoylureido)-4-cyano-3-methylthiophene-2-carboxylate (21.78 g,84%) as a brown solid. ¹H NMR (400 MHz, DMSO-d₆) δ1.54 (s, 9H), 3.58 (s,3H), 7.58 (t, J=7.5 Hz, 2H), 7.71 (t, J=7.5 Hz, 1H), 7.88 (d, J=7.5 Hz,1H), 8.05 (d, J=7.5 Hz, 2H), 12.25 (br s, 1H).

Example 64b tert-butyl 5-amino-4-cyano-3-methylthiophene-2-carboxylate

To a solution of tert-butyl 3-oxobutanoate (30 mL, 183.94 mmol) in dryEtOH (360 mL), were added elemental sulfur (5.90 g, 183.94 mmol),malononitrile (12.16 g, 183.94 mmol) and triethylamine (25.6 mL, 183.94mmol). The reaction mixture was heated to 80° C., and stirred for 2 h.After cooling to rt, the mixture was concentrated under reducedpressure. The resulting residue was dissolved in EtOAc, washed withNaHCO₃, water, brine, dried over MgSO₄, filtered and concentrated. Thecrude residue was purified by flash chromatography on silica gel (20%EtOAc in hexane) to yield tert-butyl5-amino-4-cyano-3-methylthiophene-2-carboxylate (31.2 g, 73%) as a brownsolid.

Example 65 4-Aminoquinolin-2(1H)-one

4-Amino-2-oxo-1,2-dihydroquinoline-3-carboxylic acid (Example 64) (0.030g, 0.15 mmol) was heated neat at 295° C. for 10 minutes, then cooled toroom temperature to give 4-aminoquinolin-2(1H)-one (0.023 g, 99%) as alight yellow solid. M.p.: >250° C. ¹H NMR (400 MHz, DMSO-d₆) δ5.42 (s,1H), 6.55 (s, 2H), 7.07 (t, J=7.6 Hz, 1H), 7.19 (d, J=8.0 Hz, 1H), 7.42(t, J=7.2 Hz, 1H), 7.86 (d, J=7.6 Hz, 1H), 10.71 (s, 1H). MS 161 (MH⁺).

Example 66 4-Amino-2-oxo-1,2-dihydroquinoline-3-carboxylic acid

Benzyl 4-amino-2-oxo-1,2-dihydroquinoline-3-carboxylate (Example 66a)(0.6 g, 2.04 mmol) was dissolved in DMF (8 mL) and heated at 70° C.under a hydrogen balloon in the presence of 10% Pd/C (0.15 g) for 1hour. The Pd/C was filtered out and washed with dichloromethane and thesolvents were removed under vacuum. The residue was dissolved/suspendedin NaOH (2M, 40 mL), stirred at room temperature for 30 minutes and thesolution washed with dischloromethane. The aqueous layer was cooled to0° C. and acidified to pH 1 with 2M HCl. The resultant precipitate wascollected and washed with dichloromethane to give4-amino-2-oxo-1,2-dihydroquinoline-3-carboxylic acid (0.050 g, 12%) as alight yellow solid. M.p.: >250° C. ¹H NMR (400 MHz, DMSO-d₆) δ7.32 (m,1H), 7.39 (d, J=7.6 Hz, 1H), 7.69 (m, 1H), 8.27 (d, J=8.4 Hz, 1H), 8.86(s, 1H), 9.87 (s, 1H), 11.95 (s, 1H). MS 205 (MH⁺).

Example 66a Benzyl 4-amino-2-oxo-1,2-dihydroquinoline-3-carboxylate

Benzyl 4-chloro-2-oxo-1,2-dihydroquinoline-3-carboxylate (Example 66b)(0.55 g, 1.75 mmol) was dissolved in DMF (8 mL) and 4-methoxybenzylamine(0.56 mL, 4.31 mmol) was added. The reaction was heated at 115° C. for30 minutes, then cooled to room temperature and poured into ice water.The resultant precipitate was dissolved in 10 mL TFA and stirred at roomtemperature for 15 minutes, then the mixture was poured into ice water.The resultant precipitate was collected, dissolved in dichloromethane,dried over MgSO₄, filtered and evaporated to give the crude benzyl4-amino-2-oxo-1,2-dihydroquinoline-3-carboxylate (600 mg) which was usedas this without further purification. MS 295 (MH⁺).

Example 66b Benzyl 4-chloro-2-oxo-1,2-dihydroquinoline-3-carboxylate

Dibenzylmalonate (7.75 mL, 31.6 mmol) was added slowly to a suspensionof 60% sodium hydride in mineral oil (1.41 g, 35.3 mmol) in anhydrousDMF (100 mL) at −20° C. under nitrogen. After stirring at roomtemperature for 30 minutes, isatoic anhydride (5.0 g, 30.7 mmol) wasadded, and the reaction was heated at 120° C. for 1 hour. The reactionwas then cooled to −50° C. and oxalyl chloride (10.7 mL, 123 mmol) wasslowly added. The reaction mixture was stirred at room temperature for 2hours then poured into aqueous NaCl (10%, 750 mL) at 0° C., and theresultant precipitate was filtered out. The precipitate was dissolved indichloromethane, dried over MgSO₄, filtered and evaporated under reducedpressure. Diethyl ether was added to the residue, and the resultantsolid was collected to give benzyl4-chloro-2-oxo-1,2-dihydroquinoline-3-carboxylate (3.56 g, 37% yield)which was used without further purification. MS 314 (MH⁺).

Example 67 Ethyl 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylate

Diethylmalonate (11.4 mL, 75.1 mmol) was added slowly to a suspension of60% sodium hydride in mineral oil (3.09 g, 77.3 mmol) in anhydrous DMF(100 mL) at −10° C. under nitrogen. After stirring at room temperaturefor 30 minutes, isatoic anhydride (12.0 g, 73.6 mmol) was added, and thereaction was heated at 115° C. for 2.5 hours. The reaction was cooled toroom temperature, then poured into ice water (1.4 L) and acidified to pH4 with 2M HCl. The resultant precipitate was collected, thendissolved/suspended in dichloromethane (450 mL). The dichloromethanesolution was filtered out then evaporated to provide a residue that wasvigorously triturated with diethyl ether (150 mL) for 1 hour. The solidwas collected to give ethyl4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylate (3.63 g, 21%) as awhite solid. M.p.: 190° C. ¹H NMR (400 MHz, DMSO-d₆) δ1.31 (t, J=7.2 Hz,3H), 4.35 (q, J=7.2 Hz, 2H), 7.21 (m, 1H), 7.27 (d, J=8.0 Hz, 1H), 7.63(m, 1H), 7.93 (dd, J=0.8, 8.4 Hz, 1H), 11.51 (s, 1H), 13.40 (s, 1H). MS234 (MH⁺).

Example 68 Methyl 4-amino-2-oxo-1,2-dihydroquinoline-3-carboxylate

Methyl 4-(4-methoxybenzylamino)-2-oxo-1,2-dihydroquinoline-3-carboxylate(Example 68a) (0.841 g, 2.49 mmol) was dissolved in TFA (5 mL) andstirred at room temperature for 30 minutes. The TFA was removed underreduced pressure, and the residue was dissolved in dichloromethane, thenprecipitated out by adding excess diethyl ether. The resultant solid wascollected by filtration, suspended in dichloromethane, and washed withconcentrated sodium bicarbonate. The solid was collected to give methyl4-amino-2-oxo-1,2-dihydroquinoline-3-carboxylate (0.230 g, 42%) as awhite solid. M.p.: 236° C. ¹H NMR (400 MHz, DMSO-d₆) δ3.73 (s, 3H), 7.12(t, J=8.0 Hz, 1H), 7.17 (d, J=8.0 Hz, 1H), 7.52 (t, J=8.0 Hz, 1H), 8.08(d, J=8.0 Hz, 1H), 8.38 (bs, 2H), 10.88 (bs, 1H). MS 219 (MH⁺).

Example 68a Methyl4-(4-methoxybenzylamino)-2-oxo-1,2-dihydroquinoline-3-carboxylate

Methyl 4-chloro-2-oxo-1,2-dihydroquinoline-3-carboxylate (Example 69)(0.928 g, 3.91 mmol) was dissolved in DMF (6 mL), and4-methoxybenzylamine (1.14 mL, 8.78 mmol) was added. The reaction washeated at 90° C. for 30 minutes, then cooled to room temperature andpoured into a stirred mixture of 50 mL hexanes and 100 mL ice water. Theresultant precipitate was collected by filtration and furtherchromatographed on silica gel (0% to 20% MeOH in dichloromethane) togive methyl4-(4-methoxybenzylamino)-2-oxo-1,2-dihydroquinoline-3-carboxylate as anoff white solid (0.841 g, 64%). MS 339 (MH⁺).

Example 69 Methyl 4-chloro-2-oxo-1,2-dihydroquinoline-3-carboxylate

Dimethylmalonate (2.2 mL, 19.2 mmol) was added slowly to a suspension of60% sodium hydride in mineral oil (0.81 g, 20.3 mmol) in anhydrous DMF(100 mL) at −10° C. under nitrogen. After stirring at room temperaturefor 30 minutes, isatoic anhydride (3.0 g, 18.4 mmol) was added, and thereaction mixture was heated at 115° C. for 2.5 hours. The reaction wasthen cooled to −40° C. and oxalyl chloride (6 mL, 68.8 mmol) was slowlyadded. The reaction was stirred at room temperature for 20 minutes, andwas then poured into 1200 mL of 10% NaCl at 0° C. The resultantprecipitate was collected by filtration to give crude methyl4-chloro-2-oxo-1,2-dihydroquinoline-3-carboxylate (1.40 g, 32%), whichwas used without further purification. ¹H NMR (400 MHz, DMSO-d₆) δ3.87(s, 3H), 7.39 (m, 2H), 7.70 (m, 1H), 7.92 (d, J=8.4 Hz, 1H), 12.49 (s,1H). MS 238 (MH⁺).

Example 70 Methyl 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylate

Dimethylmalonate (2.2 mL, 19.2 mmol) was added slowly to a suspension of60% sodium hydride in mineral oil (0.81 g, 20.3 mmol) in anhydrous DMF(50 mL) at −10° C. under nitrogen. After stirring at room temperaturefor 30 minutes, isatoic anhydride (3.0 g, 18.4 mmol) was added, and thereaction was heated at 115° C. for 2.5 hours. The reaction was cooled toroom temperature, then poured into ice water (500 mL) and acidified topH 2 with 2M HCl. The resultant precipitate was collected by filtrationto give crude methyl 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylate(2.89 g, 72%), which was used without further purification. ¹H NMR (400MHz, DMSO-d₆) δ3.86 (s, 3H), 7.23 (m, 2H), 7.63 (m, 1H), 7.94 (dd,J=0.8, 8.0 Hz, 1H), 11.55 (s, 1H), 13.33 (s, 1H). MS 220 (MH⁺).

Example 71 4-Amino-2-oxo-1,2-dihydroquinoline-3-carbonitrile

4-chloro-2-oxo-1,2-dihydroquinoline-3-carbonitrile (example 72) (0.66 g,3.23 mmol) was suspended in DMF (7 mL), and 4-methoxybenzylamine (0.94mL, 7.26 mmol) was added. The reaction was heated at 100° C. for 1 hourand the DMF was removed under vacuum. The residue was dissolved in TFA(6 mL) and stirred at room temperature for 30 minutes anddichloromethane (10 mL) was added. The solid product that formed wascollected, suspended in water and the solution stirred overnight. Thesolid was collected by filtration to give4-amino-2-oxo-1,2-dihydroquinoline-3-carbonitrile (0.150 g, 25%) as awhite solid. M.p.: >250° C. ¹H NMR (400 MHz, DMSO-d₆) δ7.19 (m, 2H),7.57 (m, 1H), 7.88 (bs, 2H), 8.12 (d, J=7.6 Hz, 1H), 11.23 (s, 1H). MS186 (MH⁺).

Example 72 4-chloro-2-oxo-1,2-dihydroquinoline-3-carbonitrile

2,4-dichloroquinoline-3-carbonitrile (Example 72a) (0.95 g, 4.26 mmol)and ammonium acetate (0.36 g, 4.67 mmol) were heated in acetic acid (20mL) at 140° C. for 4 hours, then cooled to room temperature. Thereaction was poured into ice water (400 mL), and the resultantprecipitate was collected by filtration to give4-chloro-2-oxo-1,2-dihydroquinoline-3-carbonitrile (0.668 g, 77%) as alight yellow solid. M.p.: >250° C. ¹H NMR (400 MHz, DMSO-d₆) δ7.42 (m,2H), 7.79 (m, 1H), 7.96 (d, J=8.4 Hz, 1H), 12.72 (s, 1H). MS 205 (MH⁺)

Example 72a 2,4-dichloroquinoline-3-carbonitrile

N-cyclohexyl-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxamide (Example73) (1.18 g, 4.12 mmol) was dissolved in phosphorus oxychloride (15 mL)and triethylamine (1.72 mL, 12.4 mmol) was slowly added. The reactionwas heated at 120° C. for 7 hours, then cooled to room temperature andpoured carefully into ice water (300 mL). The resultant precipitate wascollected by filtration to give 2,4-dichloroquinoline-3-carbonitrile(0.848 g, 92%), which was used without further purification. MS 223(MH⁺).

Example 73N-cyclohexyl-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxamide

Methyl 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylate (Example 70)(2.70 g, 12.3 mmol) was suspended in toluene (27 mL), andcyclohexylamine (1.40 g, 14.1 mmol) was added. The reaction was heatedat 115° C. for 5 hours, then cooled to room temperature. Diethyl ether(50 mL) was added, and the resultant precipitate was collected byfiltration to giveN-cyclohexyl-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxamide (1.22 g,35%) as an off white solid. M.p.: 221° C. ¹H NMR (400 MHz, DMSO-d₆)δ1.37 (m, 4H), 1.55 (m, 1H), 1.68 (m, 2H), 1.88 (m, 2H), 3.86 (m, 1H),7.28 (t, J=8.0 Hz, 1H), 7.36 (d, J=8.0 Hz, 1H), 7.68 (t, J=7.6 Hz, 1H),7.95 (d, J=8.0 Hz, 1H), 10.35 (d, J=7.6 Hz, 1H), 11.83 (bs, 1H). MS 287(MH⁺).

Example 74 4-amino-2-oxo-1,2-dihydroquinoline-3-carboxamide

N,N-bis(4-methoxybenzyl)-4-(4-methoxybenzylamino)-2-oxo-1,2-dihydroquinoline-3-carboxamide(Example 74a) (2.0 g, 3.55 mmol) was dissolved in TFA (15 mL) and thesolution was stirred at room temperature for 6 hours. The TFA wasremoved under vacuum, and the resultant solid was stirred in waterovernight, then collected by filtration to give 1.8 grams of crude finalproduct. ¹H NMR (400 MHz, DMSO-d₆) δ7.18 (m, 2H), 7.25 (d, J=7.2 Hz,1H), 7.56 (t, J=8.0 Hz, 1H), 8.09 (d, J=7.6 Hz, 2H), 9.83 (d, J=4.8 Hz,1H), 10.85 (bs, 1H), 11.12 (s, 1H). MS 204 (MH⁺).

Example 74aN,N-bis(4-methoxybenzyl)-4-(4-methoxybenzylamino)-2-oxo-1,2-dihydroquinoline-3-carboxamide

4-chloro-N,N-bis(4-methoxybenzyl)-2-oxo-1,2-dihydroquinoline-3-carboxamide(Example 74b) (4.25 g, 9.18 mmol) was dissolved in DMF (20 mL), and4-methoxybenzylamine (2.68 mL, 20.6 mmol) was added. The reaction washeated at 100° C. for 1.5 hours, then cooled to room temperature andpoured into ice water (300 mL). The resultant precipitate was collectedby filtration and further chromatographed on silica gel (0% to 20% MeOHin dichloromethane) to give crudeN,N-bis(4-methoxybenzyl)-4-(4-methoxybenzylamino)-2-oxo-1,2-dihydroquinoline-3-carboxamide(3.65 g, 71%), which was used without further purification. MS 564(MH⁺).

Example 74b4-chloro-N,N-bis(4-methoxybenzyl)-2-oxo-1,2-dihydroquinoline-3-carboxamide

Triethylamine (5.73 mL, 41.2 mmol) was added to phosphorus oxychloride(60 mL), followed by4-hydroxy-N,N-bis(4-methoxybenzyl)-2-oxo-1,2-dihydroquinoline-3-carboxamide(Example 74c) (6.11 g, 13.7 mmol). The reaction was heated at 65° C. for4 hours, then cooled to room temperature and carefully poured into icewater (1200 mL). The solution was extracted dichloromethane (2×200 mL.The organic layers were combined and washed with water, dried overMgSO₄, filtered and evaporated. The residue was dissolved indichloromethane (18 mL) and poured into 200 mL of 30% hexanes in diethylether. The resultant precipitate was collected by filtration to givecrude4-chloro-N,N-bis(4-methoxybenzyl)-2-oxo-1,2-dihydroquinoline-3-carboxamide(4.25 g, 67%) which was used without further purification. MS 463 (MH⁺).

Example 74c4-Hydroxy-N,N-bis(4-methoxybenzyl)-2-oxo-1,2-dihydroquinoline-3-carboxamide

Ethyl 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylate (Example 67)(3.58 g, 15.4 mmol) and bis(4-methoxybenzyl)amine (4.54 g, 17.6 mmol)were suspended in toluene (36 mL) and heated at 115° C. for 5 hours,then cooled to room temperature. Diethyl ether was added (50 mL), andthe resultant precipitate was collected by filtration to give crude4-hydroxy-N,N-bis(4-methoxybenzyl)-2-oxo-1,2-dihydroquinoline-3-carboxamide(6.45 g, 95%) which was used without further purification.

Example 75 4-Amino-6,7-dihydro-1H-cyclopenta[d]pyrimidin-2(5H)-one

A solution of N-(2-cyanocyclopent-1-enylcarbamoyl)benzamide (example75a) (500 mg, 1.96 mmol) and NaOH (2 N, 2.7 mL) in EtOH (20 mL) wasstirred at 100° C. under nitrogen for 2 hours. After cooling to roomtemperature, the clear reaction solution was filtered and the filtratewas carefully neutralized with 10% AcOH with vigorous stirring at 0° C.The resultant precipitate was collected by filtration, washed with warmwater and then 20% EtOH in water to give the final product4-amino-6,7-dihydro-1H-cyclopenta[d]pyrimidin-2(5H)-one (200 mg, 68%) asa white solid. ¹H NMR (400 MHz, DMSO-d₆) δ10.57 (brs, 1H), 6.93 (brs,1H), 6.65 (brs, 1H), 2.56 (t, J=7.2 Hz, 2H), 2.43 (t, J=7.6 Hz, 2H)1.96-1.89 (m, 2H). MS 152 (MH⁺).

Example 75a N-(2-cyanocyclopent-1-enylcarbamoyl)benzamide

To a solution of 2-aminocyclopent-1-enecarbonitrile (400 mg, 3.7 mmol)in 1.4-dioxane (20 mL) was added benzoyl isocyanate (545 g, 3.7 mmol).The reaction mixture was then stirred at room temperature under nitrogenovernight. The precipitate was collected by filtration, washed with1.4-dioxane, and dried to giveN-(2-cyanocyclopent-1-enylcarbamoyl)benzamide (720 mg, 76%) as a whitesolid. ¹H NMR (400 MHz, CDCl₃) δ11.33 (s, 1H), 11.22 (brs, 1H),7.99-7.97 (m, 2H), 7.67-7.63 (m, 1H), 7.54-7.51 (m, 2H), 3.04-3.0 (m,2H), 2.51-2.47 (m, 2H) 1.95-1.90 (m, 2H). MS 256 (MH⁺).

Example 764-amino-6,7,8,9-tetrahydro-1H-cyclohepta[d]pyrimidin-2(5H)-one

Prepared as in example 75 from(Z)—N-(2-cyanocyclohept-1-enylcarbamoyl)benzamide (Example 76a). ¹H NMR(400 MHz, DMSO-d₆) δ10.29 (brs, 1H), 6.72 (brs, 2H), 2.49-2.46 (m, 2H),2.38-2.36 (m, 2H) 1.72-1.66 (m, 2H), 1.52-1.48 (m, 2H) 1.41-1.36 (m,2H). MS 180 (MH⁺).

Example 76a (Z)—N-(2-cyanocyclohept-1-enylcarbamoyl)benzamide

Prepared as in Example 75a from (Z)-2-aminocyclohept-1-enecarbonitrileand benzoyl isocyanate as a white solid. MS 284 (MH⁺).

Experiment 4 Biological Assay

An HEK293 cell line derivative (Chandrashekar et al., Cell 100, 703-711,2000) which stably expresses Gα15 and hT1R2/hT1R3 (Li et al., Proc NatlAcad Sci USA 99, 4692-4696, 2002) (see also, International PublicationNo. WO 03/001876) was used in biological assays in association withidentifying compounds with sweet taste enhancing properties.

Compounds were initially selected based on their activity on thehT1R2/hT1R3-HEK293-Gα15 cell line Li et al., supra. Activity wasdetermined using an automated fluorometric imaging assay on a FLIPRinstrument (Fluorometric Intensity Plate Reader, Molecular Devices,Sunnyvale, Calif.) (designated FLIPR assay). Cells from one clone(designated clone S-9) were seeded into 384-well plates (atapproximately 50,000 cells per well) in a medium containing DMEM LowGlucose (Invitrogen, Carlsbad, Calif.), 10% dialyzed fetal bovine serum(Invitrogen, Carlsbad, Calif.), 100 Units/ml Penicillin G, and 100 μg/mlStreptomycin (Invitrogen, Carlsbad, Calif.) (Li et al., 2002) (see also,International Publication No. WO 03/001876).

S-9 cells were grown for 24 hours at 37° C. S-9 cells were then loadedwith the calcium dye Fluo-3 AM (Molecular Probes, Eugene, Oreg.), 4 μMin a phosphate buffered saline (D-PBS) (Invitrogen, Carlsbad, Calif.),for 1 hour at room temperature. After replacement with 25 μl D-PBS,stimulation was performed in the FLIPR instrument and at roomtemperature by the addition of 25 μl D-PBS supplemented with compoundsat concentrations corresponding to three times the desired final level(Stimulation 1).

Cells were incubated with the compounds for 7.5 minutes and then anotherstimulation was performed in the FLIPR instrument by the addition of 25μl of D-PBS supplemented with a sub-optimal concentration of sweeteners(producing about 5% to 20% receptor activity) (Stimulation 2).

Alternatively after replacement with 25 μl D-PBS per well, stimulationwas performed in the FLIPR instrument at room temperature by addition of25 μl D-PBS supplemented with different stimuli.

Typical sweeteners used include, but are not limited to D-Glucose,D-Fructose, Sucralose, Aspartame and Sucrose. Receptor activity was thenquantified by determining the maximal fluorescence increases (using a480 nm excitation and 535 nm emission) after normalization to basalfluorescence intensity measured before stimulation. Compounds producingan increase in sweetener-mediated receptor activity were chosen forfurther characterization and quantification of potential enhancementproperties.

In this follow assay, a fixed concentration of compounds was added induplicates to 10 consecutive columns (20 wells total) duringstimulation 1. Typical compound concentrations tested were 300 μM, 100μM, 50 μM, 30 μM, 10 μM, 3 μM and 1 μM, 0.3 μM, 0.1 μM, or 0.03 μM.After the 7.5 minute incubation period, increasing concentrations ofsweetener (to generate a dose-response curve) was presented in the samewells, in duplicates, during stimulation 2. The relative efficacy ofcompounds at enhancing the receptor was determined by the calculatingthe magnitude of a shift in the EC₅₀ for the sweetener. Enhancement wasdefined as a ratio (EC₅₀R) corresponding to the EC₅₀ of sweeteners,determined in the absence of the test compound, divided by the EC₅₀ ofthe sweetener, determined in the presence of the test compound. In someembodiments, compounds have an EC₅₀R between about 1 (e.g., >1) andabout 1000. In other embodiments, compounds have an EC₅₀R between about1.25 and about 500. In still other embodiments, compounds have an EC₅₀Rbetween about 1.50 and about 100. In yet other embodiments, compoundshave an EC₅₀R between about 1 (e.g., >1) and about 50.

In still other embodiment, compounds at about 50 μM have an EC₅₀Rbetween about 1 (e.g., >1) and about 1000, between about 1.25 and about500, between about 1.50 and about 100, or between about 1 (e.g., >1) andabout 50. Assay results for compounds are illustrated in the tablebelow.

Compound Pre-incubated Sucralose Co-stimulation Sucralose Number EC₅₀R(50 μM) EC₅₀R (50 μM) 300 5.20 4.46 301 2.41 1.93 302 2.19 2.44 303 2.193.77 304 1.73 4.14 305 1.58 2.98 306 1.00 1.32 307 1.02 1.38 308 1.121.12 309 1.11 1.07 310 0.86 1.01 311 1.08 1.11 312 0.73 0.78 313 0.950.97 314 1.11 1.06 315 0.84 1.05 316 0.99 1.11 317 0.90 1.04 318 0.86319 1.03 1.09 320 1.06 322 0.92 0.98 323 1.10 1.89 324 0.87 1.12 3251.10 326 0.99 327 0.86 328 0.96 329 0.72 330 1.16 331 1.25 332 1.03 1.35333 0.87 1.36 334 1.23 0.74 335 0.99 336 0.99 337 0.90 0.96 338 0.93 3391.07 340 0.89 341 0.82 342 1.15 1.02 343 0.98 1.35

Experiment 5 Sweet Flavor and Sweet Flavor Enhancement Measurement UsingHuman Panelists

Test samples containing experimental compounds were compared to adose-response curve for perceived sweetness intensity of sucraloseconcentrations to determine equivalent sweetness intensity.

A group of eight or more panelists tasted solutions including sucraloseat various concentrations, as well as the experimental compound bothwith and without added sucralose. Panelists then rated sweetnessintensity of all samples on a structured horizontal line scale, anchoredfrom 0 to 15, where 0 equals no sweetness and 15 equals equivalentsweetness to a 15% sucrose sample. Scores for sweetness intensity wereaveraged across panelists. Then using the average scores and/or equationof the line for the sucralose dose-response curve, equivalent sweetnesssucralose concentrations were determined for the samples containingexperimental compounds.

Subjects had been previously familiarized with the key attribute tasteand were trained to use the 0 to 15 point line scale. Subjects refrainedfrom eating or drinking (except water) for at least 1 hour prior to thetest. Subjects ate a cracker and rinsed with water several times toclean the mouth.

Sucralose solutions were provided at a wide range of concentrations,such as 100 ppm, 200 ppm, 300 ppm, 400 ppm, and 500 ppm in order tocreate a dose-response curve. Samples containing experimental compoundwere prepared both alone and in a 100 ppm sucralose solution. Allsamples were made up in low sodium buffer pH 7.1. In order to aiddispersion, solutions can be made up in 0.1% ethanol.

The solutions were dispensed in 20 ml volumes into 1 oz. sample cups andserved to the subjects at room temperature. All samples were presentedin randomized counterbalanced order to reduce response bias. Further,two sessions of testing may be used to check panel precision.

Subjects tasted each sample individually and rate sweetness intensity onthe line scale prior to tasting the next sample. All samples wereexpectorated. Subjects may retaste the samples but can only use thevolume of sample given. Subjects must rinse with water between samples.Eating an unsalted cracker between samples may be required depending onthe samples tasted.

The scores for each sample were averaged across subjects and standarderror was calculated. The dose-response curve was plotted graphically,and this may be used to ensure the panel is rating accurately; i.e.,increasing the concentration of sucralose should correspond to increasedaverage scores for sweetness. A 2-way ANOVA (factors being samples andpanelists) and multiple comparison tests (such as Tukey's HonestlySignificant Difference test) can be used to determine differences amongsamples and/or panelists. A 3-way ANOVA, with sessions as the thirdfactor, can be used to determine if there is any difference in theratings between sessions.

The results of human taste tests with a compound 7 are found below.Table 1 indicates that 100 μM compound 7 in 100 ppm sucralose hassweetness equivalent to 200 ppm sucralose. Table 2 indicates that 100 μMcompound 7 alone has no sweetness, and therefore can be defined as atrue sweet enhancer.

TABLE 1 Average sweetness scores for various sucralose samples,including 100 ppm sucralose with 100 μM compound 7, n = 32 (16 Panelists× 2 replicates). Tukey's Value = 1.409 (α = 0.05). Standard Tukey's HSDSample Average Error Significance (5%) 100 ppm Sucralose 6.3 0.3 A 100ppm Sucralose + 100 μM 7 10.2 0.5 B 200 ppm Sucralose 10.4 0.5 B 300 ppmSucralose 11.5 0.4 Bc 400 ppm Sucralose 12.3 0.4 C

TABLE 2 Average sweetness scores for 100 μM compound 7 and low sodiumbuffer, n = 15 (15 Panelists × 1 rep). Tukey's Value = 0.186 (α = 0.05).Standard Tukey's HSD Sample Average Error Significance (5%) Low SodiumBuffer 0.1 0.1 A (contains no sweeteners) 100 μM 7 0.1 0.1 A

The results of human taste tests with compound 1 are found below. Table3 indicates that 100 μM compound in 100 ppm sucralose has sweetnessequivalent to about 600 ppm sucralose. Table 4 shows a dose responsecurve of compound 1 with 100 ppm sucralose which shows that thesweetness of sucralose is significantly enhanced by addition ofincreasing amounts of compound 1. Table 5 indicates that 100 μM compound1 alone has little or no sweetness, and therefore can be defined as atrue sweet enhancer.

TABLE 3 Average sweetness scores, n = 12 (12 Panelists × 1 rep). Tukey'sValue = 2.449 (α = 0.05), 2.209 (α = 0.10). Treatment Average SD St ErTukey (5%) Tukey (10%) 100 ppm Sucralose 7.4 1.7 0.5 a a 200 ppmSucralose 10.4 1.9 0.6 b b 300 ppm Sucralose 10.5 2.8 0.8 b b 400 ppmSucralose 11.2 2.4 0.7 bc bc 600 ppm Sucralose 13.0 1.4 0.4 c c 100 μM1 + 13.3 1.6 0.5 c c 100 ppm Sucralose

TABLE 4 Average sweetness scores, n = 26 (14 Panelists × 1 rep; 12panelists × 1 rep). Tukey's Value = 1.584 (α = 0.05), 1.452 (α = 0.10).Treatment Average SD St Er Tukey (5%) Tukey (10%) 100 ppm sucralose 6.31.5 0.3 a a 100 ppm sucralose + 7.4 1.7 0.3 ab ab 3.12 μM 1 100 ppmsucralose + 8.4 1.8 0.4 bc bc 6.25 μM 1 100 ppm sucralose + 9.1 1.9 0.4cd cd 12.5 μM 1 200 ppm sucralose 9.5 2.0 0.4 cd cd 300 ppm sucralose10.3 2.7 0.5 d d 100 ppm sucralose + 10.3 1.6 0.3 d d 25 μM 1 400 ppmsucralose 12.1 1.9 0.4 e e 100 ppm sucralose + 12.3 1.5 0.3 e e 50 μM 1

TABLE 5 Average sweetness scores, n = 12 (12 Panelists × 1 rep). Tukey'sValue = 0.809 (α = 0.05), 0.723 (α = 0.10). Treatment Average SD St ErTukey (5%) Tukey (10%) 0% Sucrose 0.0 0.0 0.0 a a 100 uM 1 in LSB 0.20.3 0.1 a a 2% Sucrose 2.4 1.0 0.3 b b

The results of human taste tests with compound 149 are found below.Table 6 indicates that 100 μM compound in 100 ppm sucralose hassweetness equivalent to about between 200 and 300 ppm sucralose. Table 7indicates that 100 μM compound 149 alone has no sweetness, and thereforecan be defined as a true sweet enhancer.

TABLE 6 Average sweetness scores, n = 13 (13 Panelists × 1 rep). Tukey'sValue = 2.333 (α = 0.05), 2.087 (α = 0.10). Treatment Average SD St ErTukey (5%) Tukey (10%) 100 ppm Sucralose 6.5 1.3 0.4 a a 200 ppmSucralose 9.1 2.0 0.6 b b 100 ppm Sucralose + 9.8 1.8 0.5 b bc 100 μM149 300 ppm Sucralose 10.8 2.8 0.8 b bc 400 ppm Sucralose 11.2 2.3 0.6 bc

TABLE 7 Average sweetness scores, n = 13 (13 Panelists × 1 rep). Tukey'sValue = 0.906 (α = 0.05), 0.811 (α = 0.10). Treatment Average SD St ErTukey (5%) Tukey (10%) 100 uM 149 in LSB 0.0 0.0 0.0 a a 0% Sucrose 0.00.1 0.0 a a 2% Sucrose 1.8 1.0 0.3 b b

The invention claimed is:
 1. A method of enhancing the sweet taste of acomestible composition comprising contacting the comestible compositionwith a compound of Formula (IIa):

or a pharmaceutically acceptable salt thereof; wherein: A is hydrogen,alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl, substitutedarylalkyl, heteroaryl, substituted heteroaryl, heteroarylalkyl,substituted heteroarylalkyl, —CN, —OR⁹, —S(O)_(c)R⁹, —NR⁹COR¹⁰, —NHOR⁹,—NR⁹R¹⁰, —CONR⁹R¹⁰, —CO₂R⁹, —NR⁹CO₂R¹⁰, —NR⁹CONR¹⁰R¹¹, —NR⁹CSNR¹⁰R¹¹, or—NR⁹C(═NH)NR¹⁰R¹¹; R¹⁷ is hydrogen, alkyl, or substituted alkyl; B is—N—; Y forms a single bond with W and a double bond with Z; W is —S—; Yis —C(R²⁶)—; Z is —C(R²⁷)—; R²⁶ is hydrogen, alkyl, substituted alkyl,aryl, substituted aryl, arylalkyl, substituted arylalkyl, acyl,substituted acyl, heteroalkyl, substituted heteroalkyl, heteroaryl,substituted heteroaryl, heteroarylalkyl, substituted heteroarylalkyl,—OR³¹, —OCOR³¹, —NR³¹R³², —CONR³¹R³², or —CO₂R³¹; R²⁷ is hydrogen,alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl, substitutedarylalkyl, acyl, substituted acyl, heteroalkyl, substituted heteroalkyl,heteroaryl, substituted heteroaryl, heteroarylalkyl, substitutedheteroarylalkyl, —OR³³, —OCOR³³, —NR³³R³⁴, —CONR³³R³⁴, or —CO₂R³³; R⁹,R¹⁰, R¹¹, R¹⁹, R³¹, R³², R³³, and R³⁴ are independently hydrogen, alkyl,substituted alkyl, aryl, substituted aryl, arylalkyl, substitutedarylalkyl, heteroalkyl, substituted heteroalkyl, heteroaryl, substitutedheteroaryl, heteroarylalkyl or substituted heteroarylalkyl;alternatively R⁹ and R¹⁰, R¹⁰ and R¹¹, R³¹ and R³², or R³³ and R³⁴,together with the atoms to which they are bonded, form acycloheteroalkyl or substituted cycloheteroalkyl ring; wherein thesubstituted acyl, substituted alkyl, substituted cycloheteroalkyl,substituted aryl, substituted arylalkyl, substituted heteroalkyl,substituted heteroaryl, and substituted heteroarylalkyl, and substitutedcycloheteroalkyl each independently comprises one or more substituentgroups selected from the group consisting of —R^(a), halo, ═O, —OR^(b),—SR^(b), ═S, —NR^(c)R^(c), ═NR^(b), ═N—OR^(b), trihalomethyl, —CN, —NO₂,—S(O)₂R^(b), —S(O)₂NR^(b), —S(O)₂OR^(b), —OS(O)₂R^(b), —OS(O)₂OR^(b),—P(O)(OR^(b))(OR^(b)), —C(O)R^(b), —C(NR^(b))R^(b), —C(O)OR^(b),—C(O)NR^(c)R^(c), —C(NR^(b))NR^(c)R^(c), —OC(O)R^(b), —OC(O)OR^(b),—NR^(b)C(O)R^(b), —NR^(b)C(O)OR^(b), —NR^(b)C(O)NR^(c)R^(c),—NR^(b)C(NR^(b))R^(b) and —NR^(b)C(NR^(b))NR^(c)R^(c), where R^(a) isselected from the group consisting of alkyl, cycloalkyl, heteroalkyl,cycloheteroalkyl, aryl, arylalkyl, heteroaryl and heteroarylalkyl; eachR^(b) is independently hydrogen or R^(a); and each R^(c) isindependently R^(b) or alternatively, the two R^(c)s are taken togetherwith the nitrogen atom to which they are bonded form a 4-, 5-, 6- or7-membered cycloheteroalkyl; and the comestible composition comprises atleast one sweetener selected from the group consisting of sucrose andsucralose.
 2. The method of claim 1, wherein A is hydrogen, alkyl,substituted alkyl, aryl, substituted aryl, arylalkyl, substitutedarylalkyl, heteroaryl, substituted heteroaryl, heteroarylalkyl,substituted heteroarylalkyl, —CN, —S(O)_(c)R⁹, —NR⁹R¹⁰, —CONR⁹R¹⁰,—CO₂R⁹, or —NR⁹CO₂R¹⁰.
 3. The method of claim 1, wherein A is hydrogen,alkyl, substituted alkyl, aryl, substituted aryl, —CN, —S(O)_(c)R⁹,—NR⁹R¹⁰, —CONR⁹R¹⁰, —CO₂R⁹, or —NR⁹CO₂R¹⁰.
 4. The method of claim 1,wherein R¹⁷ is hydrogen, alkyl, or substituted alkyl.
 5. The method ofclaim 1, wherein A is hydrogen, alkyl, substituted alkyl, aryl,substituted aryl, —CN, —S(O)_(c)R⁹, —NR⁹COR¹⁰, —NR⁹R¹⁰, —CONR⁹R¹⁰,—CO₂R⁹, or —NR⁹CO₂R¹⁰; and R¹⁷ is hydrogen, alkyl, or substituted alkyl.6. The method of claim 1, wherein R²⁶ is hydrogen, alkyl, substitutedalkyl, acyl, substituted acyl, heteroalkyl, substituted heteroalkyl,—OR³¹, —OCOR³¹, —NR³¹R³², —CONR³¹R³² or —CO₂R³¹; and R²⁷ is hydrogen,alkyl, substituted alkyl, acyl, substituted acyl, heteroalkyl,substituted heteroalkyl, —OR³³, —OCOR³³, —NR³³R³⁴, —CONR³³R³⁴ or—CO₂R³³.
 7. The method of claim 1, wherein R²⁶ is hydrogen, alkyl, orsubstituted alkyl; and R²⁷ is hydrogen, alkyl, or substituted alkyl. 8.The method of claim 1, wherein A is hydrogen, alkyl, substituted alkyl,aryl, substituted aryl, —CN, —NO₂, —S(O)_(c)R⁹, —NR⁹R¹⁰, —CONR⁹R¹⁰,—CO₂R⁹ or —NR⁹CO₂R¹⁰; R¹⁷ is hydrogen, alkyl, or substituted alkyl; R²⁶is hydrogen, alkyl, substituted alkyl, acyl, substituted acyl,heteroalkyl, substituted heteroalkyl, —OR³¹, —OCOR³¹, —NR³¹R³²,—CONR³¹R³² or —CO₂R³¹; and R²⁷ is hydrogen, alkyl, substituted alkyl,acyl, substituted acyl, heteroalkyl, substituted heteroalkyl, —OR³³,—OCOR³³, —NR³³R³⁴, —CONR³³R³⁴ or —CO₂R³³.
 9. The method of claim 1,wherein A is —OH, —NH₂, —NHCH₃, —N(CH₃)₂, —NHOCH₃, —NHC(O)CH₃,—NHC(O)OCH₃, —NHC(O)NH₂, —NHC(S)NH₂, —NHC(NH)NH₂, —CN, —CH₂OH, —CH₂NH₂,—CH₂NHCH₃, —CH₂N(CH₃)₂, —CO₂H, —CONH₂, —CONHCH₃ or —CH₂NHC(O)CH₃; R¹⁷ ishydrogen, methyl, ethyl, propyl, iso-propyl, n-butyl, iso-butyl,sec-butyl, t-butyl, or benzyl; R²⁶ is hydrogen, —CF₃, methyl, ethyl,propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl or t-butyl; and R²⁷ ishydrogen, —CF₃, methyl, ethyl, propyl, iso-propyl, n-butyl, iso-butyl,sec-butyl or t-butyl.
 10. The method of claim 1, wherein the compound isselected from the group consisting of

or a pharmaceutically acceptable salt thereof.
 11. The method of claim1, wherein the compound has a concentration from 0.0001 ppm to 10 ppm.12. The method of claim 1, wherein the compound has a concentration from0.0001 ppm to 100 ppm.
 13. The method of claim 1, wherein the compoundhas a concentration from 0.01 ppm to 100 ppm.
 14. The method of claim 1,wherein the comesible composition is a food or beverage product.
 15. Themethod of claim 14, wherein the food or beverage product is selectedfrom the group consisting of confectioneries, bakery products, dairyproducts, sweet and savory snacks, meal replacement products, readymeals, soups, pastas, noodles, canned foods, frozen foods, dried foods,chilled foods, oils and fats, baby foods, spreads, a cooking aidproduct, a meal solution product, a meal enhancement product, aseasoning, a seasoning blend, cake, cookie, pie, candy, chewing gum,gelatin, ice creams, sorbet, pudding, jam, jelly, salad dressing,condiments, cereals, canned fruits, fruit sauces, a carbonated ornon-carbonated beverage, a beverage mix, a beverage concentrate, soda,juice, an alcoholic beverage, and combinations thereof.